Can your laptop battery be overcharged

dgzntdMost laptops today use lithium Ion (Li-ion) batteries. Overcharging Li-ion batteries is not a problem and does not affect the battery life span. These batteries can be charged 300 to 500 times, and they have an internal circuit to stop the charging process at full charge. The control system prevents overcharging, which can cause the lithium ion battery to overheat and potentially burn. This is why the Li-ion batteries are more expensive. The only way for the Li-ion battery to overcharge is if the charging system malfunctions, and then the battery will heat up while in the charger. If you don’t plan to use your laptop for long period of time, you can extend the life of your lithium ion laptop battery by storing it with a 50 percent charge. A fully discharged battery left for a long period of time will lose its charging capacity. Fully charged batteries discharge when they are left unused, and will lose effectiveness. This is why it is recommended to discharge a Li-ion battery until it is almost out before shutting down. Running a Li-ion battery down completely will diminish capacity. Keep the battery in a cool place and do not store your computer for a long period of time while it is fully charged.

Older laptops use Nickel-cadmium (Ni-Cd) and Nickel Metal Hydride (Ni-MH) batteries. They require more maintenance than Lithium Ion batteries. They must be fully discharged and then fully recharged so that they don’t lose battery life. These batteries can be overcharged only if they go through too many cycles of charging and discharging, which reduces their effectiveness and capacity. It is better to charge all batteries fully before use; then use on battery power until the optimum level for each battery type is reached, before recharging.

Why are Macs thought to be better than PCs

fdhgfnIt was February 1981. Nearly half of the Apple II engineering team at Apple Computer had been fired the previous day, and now the company’s CEO, Steve Jobs, was peering over the wall of programmer Andy Hertzfeld’s cubicle.

Hertzfeld was typing code for Apple II’soperating system when Jobs rounded the corner, yanked the computer’s power cord out of the socket and carted the machine — with Hertzfeld in tow — from the corporate campus to a small office overlooking a Texaco station in Cupertino, Calif.

Hertzfeld wasn’t fired; he was promoted.

He would spend his days authoring code for Apple’s new Macintosh project [source: Hertzfeld]. The team had only a few months to create a new operating system that would be faster and more efficient — and become the predecessor of today’s iMacs.

The abrupt reassignment and truncated schedule were a workplace phenomenon Apple employees knew as a “reality distortion field.” This Star Trek term was used to describe Jobs’ ability to convince nearly anyone to do nearly anything — and deliver it according to an unrealistic timetable [source: Hertzfeld].

Regardless of whether Jobs really could bend the time-space continuum, his drive and personality helped Apple Computers change the way people use technology. It was one of the first companies to transform the computer from an imperceptible mass of vacuum tubes stationed primarily at universities and government offices to a manageable-sized machine for ordinary people.

Today, Apple is as relevant as ever, thanks to new releases of Apple operating systems, software and hardware, and related products like the iPod, iPhone and iPad.

Apple products are vertically integrated; the company makes its own hardware, software and accessories, and delivers the product whole to the consumer [source: Dalakov]. Instead of making decisions about what components and software to use and then manually installing them, Mac users can simply power up their computers and use them right out of the box. And if they have a problem with any component — from keyboard to hard drive — there’s a single point of contact at Apple’s customer service.

By contrast, PCs have hardware and software components made by multiple outside vendors. Users may need to communicate with several vendors to diagnose and fix a PC problem. However, being able to pick and choose components also makes PCs easier to customize than Macs in terms of both cost and capabilities [source: Nutter].

The ability to migrate information between Macs and PCs can be challenging because of each system’s inherent differences. Macs are considered a “closed” system because their components — software, hardware, operating systems — are not compatible with non-Macs [source: Chaffin]. However, non-Apple-developed apps, accessories and even operating systems are becoming increasingly Mac-accessible.

Macs have a reputation for being more expensive than PCs, but feature-by-feature breakdowns have shown that show the fees are quite comparable. Building a laptop with similar features as a MacBook Pro, for example, may cost as much or more [source: Finnie].

For some Mac fans, however, price is not the point. It may be the lingering effects of reality distortion, but Apple’s managed to create a computer with a virtual federation of loyal fans.

The Best Ways to Clean Your Computer Keyboard

xhykjykOne of the best ways to keep a keyboard in top condition is periodic cleaning. As preventive maintenance, you should vacuum the keyboard weekly, or at least monthly. When vacuuming, you should use a soft brush attachment to dislodge the dust. Also note that some keyboards have keycaps that come off easily, so be careful when vacuuming; otherwise you may have to dig the keys out of the vacuum cleaner. I recommend using a small, handheld vacuum cleaner made for cleaning computers and sewing machines; these have enough suction to get the job done with little risk of removing your keytops.

You also can use compressed air to blow the dust and dirt out instead of using a vacuum. Before you dust a keyboard with the compressed air, however, power off the computer, unplug the keyboard, and turn it upside down so the particles of dirt and dust collected inside can fall out.

On most keyboards, each keycap is independently removable, which can be handy if a key sticks or acts erratically. For example, a common problem is a key that does not work every time you press it. This problem usually results from dirt collecting under the key. An excellent tool for removing keycaps on almost any keyboard is the U-shaped chip puller included in many computer tool kits. Simply slip the hooked ends of the tool under the keycap, squeeze the ends together to grip the underside of the keycap, and lift up. IBM sells a tool designed specifically for removing keycaps from its keyboards, but the chip puller works even better. After removing the cap, spray some compressed air into the space under the cap to dislodge the dirt. Then replace the cap and check the action of the key.

When you remove the keycap on some keyboards, you are actually detaching the entire key from the keyswitch. Be careful during the removal and reassembly of the keyboard; otherwise, you’ll break the switch. The classic IBM/Lexmark-type Model M keyboards (now made by Unicomp) use a removable keycap that leaves the actual key in place, enabling you to clean under the keycap without the risk of breaking the switches. If you don’t want to go through the effort of removing the keycaps, consider using cleaning wands with soft foam tips to clean beneath the keytops.

Spills can be a problem, too. If you spill a soft drink or cup of coffee into a keyboard, you do not necessarily have a disaster. Many keyboards that use membrane switches are spill resistant. However, you should immediately (or as soon as possible) disconnect the keyboard and flush it out with distilled water. Partially or fully disassemble the keyboard and use the water to wash the components. If the spilled liquid has dried, soak the keyboard in some of the water for a while. When you are sure the keyboard is clean, pour another gallon or so of distilled water over it and through the keyswitches to wash away any residual dirt. After the unit dries completely it should be perfectly functional. You might be surprised to know that drenching your keyboard with water does not harm the components. Just make sure you use distilled water, which is free from residue or mineral content. (Bottled water is notdistilled; the distinct taste of many bottled waters comes from the trace minerals they contain!) Also, make sure the keyboard is fully dry before you try to use it; otherwise, some of the components might short out.

Fully drying a keyboard that has been soaked in water can take several days or more, so be prepared to wait. You can use compressed air to greatly speed up the drying process. Even then, if the contaminants were not fully flushed out, the keyboard may still not work correctly. In that case the best results will be obtained by completely disassembling the keyboard, washing and then drying each component individually, and then reassembling. Depending on the value and construction of the keyboard, a replacement may be the best option.

How To Cope With A Cash Advance

Get instant $ 700 www.My cash Charlotte North Carolina low interest Get $700 tonight fast wire transfer. You can also apply urgent $ 1000 Mobile, AL within one day .

Payday loans are a kind of financial loan that lots of people are knowledgeable about, but have in no way experimented with as a result of anxiety. The fact is, there is certainly absolutely nothing to hesitate of, with regards to online payday loans. Pay day loans will be helpful, as you will see with the suggestions in the following paragraphs.

Bear in mind that if you do not shell out your payday loan back again by the due date, the sum you go should go into series. Subsequently, your credit score will be affected. It is essential that your banking account has ample money during the day you already know the business will probably be getting their money.

In case you are looking for a pay day loan the very first time, determine in case the lender sets a limit on how much cash you can obtain. Many businesses could have a cover on your own initial payday loan. Then will allow you to borrow a lot more together with your 2nd, or thirdly financial loan.

Phone around and find out interest rates and service fees. Most cash advance firms have similar service fees and rates of interest, yet not all. You may be able to conserve 10 or fifteen $ $ $ $ on your own financial loan if someone company provides a reduced monthly interest. When you often get these lending options, the financial savings will prove to add up.

It is necessary to never use payday loans to fund deluxe things, like TV’s or getaways. They are finest used in cases where there is an unexpected emergency, or perhaps a expenses you cannot pay out punctually. Should you need cash for luxury goods, it is far better to consider financing from the financial institution, or a lower-fascination visa or mastercard. The fascination charged on this kind of credit will almost always be less than a cash advance.

If you are working for yourself, you might like to apply for a attached private bank loan rather than a payday loan. Simply because online payday loans are almost never given to personal-employed individuals. Cash advance service providers have to see evidence of regular cash flow and free lance men and women normally have unforeseen earnings, and they are typically unable to supply evidence of long term revenue.

When you are trying to get a cash advance online, ensure that you get in touch with and speak with an agent before going into any information and facts in to the site. Numerous crooks pretend to become cash advance agencies to obtain your hard earned money, so you want to ensure that you can reach an authentic person.

There are actually payday cash loans readily available that do not require faxing any forms, but know that these sorts of loans feature a huge find. You will have to shell out much more for your deluxe of having a quicker bank loan. Because of this the rates and service fees are much beyond other manufacturers.

Think away from box when it comes to repaying your cash advance as quickly as you can. Are there any alternatives you can now use that maybe had been not available before you take out your financial loan? Exist family or close friends it is possible to phone to borrow dollars? Can you receive a decrease fascination financial loan by placing a great-worth product it is possible to for the short term live without in a pawn retail outlet? Be worthwhile the payday loan as fast as it is possible to.

Be sure to pick your cash advance very carefully. You should think about how long you will be given to pay back the financing and exactly what the interest rates are just like before choosing your payday loan. See what your best options are and then make your selection to avoid wasting dollars.

An excellent element of payday cash loans is the fact there is no need to obtain a credit examine or have equity to obtain financing. A lot of cash advance companies do not require any qualifications other than your proof of work. Ensure you take your pay stubs with you when you go to sign up for the financing.

With a little luck, this article has you well armed being a buyer, and well-informed concerning the information of payday loans. Exactly like everything else in the world, you can find positives, and downsides. The ball is at your courtroom as being a buyer, who have to find out the facts. Weigh them, and make the best decision!

Does adding more RAM to your computer make it faster

One topic you might hear people discussing when they’re talking shop about computers is how much random access memory (RAM) they need to add to their computer. Up to a point, adding RAM will normally cause your computer to seem faster on certain types of operations. RAM is important because it eliminates the need to “swap” programs in and out.

When you run a program such as a word processor or an Internet browser, the microprocessor in your computer pulls the executable file (.exe) off the hard disk and loads it into RAM. Large programs like Microsoft Word or Excel use large amounts ofmemory. The microprocessor also pulls in a number of shared dynamic link libraries (DLLs) — shared pieces of code used by multiple applications. The DLLs take many more megabytes.

Then the microprocessor loads in the data files at which you want to look, which might total several megabytes if you are looking at more than one document or browsing a page with a lot of graphics. So a big application can easily take 100 megabytes of RAM or more, which can slow your system down significantly if there isn’t enough memory. On your machine, at any given time you might have the following applications running:

  • ­­­A word processor
  • A spreadsheet
  • An e-mail program
  • A drawing program
  • Three or four browser windows
  • A fax program
  • A Telnet session

Besides all of those applications, the operating system itself is taking up a good bit of space. Everything together may need more RAM than your machine has.

How Printable Computers Will Work

Few argue that the next generation of computers will be nearly invisible, meaning that they will blend in with everyday objects. Flexible ink-like circuitry will be printed onto plastic or sprayed onto various other substrates, such as clothes. One of the scientists leading this printable computer revolution is Joseph Jacobsonof MIT Media Lab’s Nano Media Group. Jacobson has said that his group will be able to produce a simple printed microprocessor in late 2001 or early 2002. He also foresees being able to eventually produce a printed chip that could rival anIntel Pentium processor.

Jacobson’s group has already succeeded in using an ordinary Hitachi ink jet printer to make several components for a printable computer. Using a nanoparticle-based inkmade from suspending nano-size semiconductor particles in a liquid, researchers spray the components onto a plastic substrate. Here’s a look at some of the printed components the MIT group has made with this process:

  • Thermal actuators — An actuator is a sensor that causes a device to be turned on, off, adjusted or moved. In a thermal actuator, heat is used to cause the expansion of components to create movement.
  • Linear-drive motors — This type of motor is similar to a normal electric motor, which has a magnet that circles around the coil loop to make the motor spin. However, there is one key difference. Think of linear-drive motors as flattened electric motors containing a flat magnet moving back and forth across a coil. In a sense, the magnet in the linear drive motor acts like a piston.
  • Microelectromechanical Systems (MEMS) — MEMS are touted as the precursor or bridge to nanotechnology. These micromachines are used in a variety of devices, including pacemakers, games, and accelerometers of airbags. They perform a variety of functions, including sensing, communication and actuation. In the future, MEMS are expected to have the ability to self-replicate.

The Media Lab also created transistors using a different process. For that, polymer stamps are used with the architecture of the transistors in a positive relief. The stamp is then dipped in the nanoparticle ink and transferred to a substrate by hand. The next step will be to use an ink jet printer or some other kind of desktop fabricator to create printable transistors.

MIT isn’t the only group developing ways to print computer circuitry. Plastic Logic, a company that sprang out of work begun at Cambridge University in England, plans to market the first plastic chip. The company has developed and patented a method of printing plastic onto polymer substrates, making cheap and flexible plastic transistors. The process is similar to the ink jet process used by MIT, but Plastic Logic adds carbon-based chemicals to alter the properties of the plastic. By printing the chips onto rolls of film, they can be applied to a variety of surfaces.

At Lucent Technologies’ research company, Bell Labs Innovations, researchers developed the world’s first printed transistor in 1997. Using plastic sheets similar to overhead projector transparencies, a liquid plastic semiconductor is applied over a stainless-steel mesh with a squeegee to form the multiple layers of the transistor. After the solvent of the mixture evaporates, the plastic remains. The process is very similar to how silk screening works. Lucent has teamed up with E Ink, an MIT offspring, to create printable displays. See How Electronic Ink Will Work for more information.

Soon, scientists will be able to create just about every part of a computer’s hardware using a desktop fabricator. Plastic will take the place of silicon for many purposes, but don’t expect to write off silicon as a valuable computer component for at least a decade or two. In the next section, we’ll see how plastic stacks up against silicon and why we can expect silicon to stick around for many more years.

Upgrading a Flash BIOS

Virtually all PCs built since 1996 use a flash ROM to store the BIOS. A flash ROM is a type of EEPROM chip you can erase and reprogram directly in the system without special equipment. Older EPROMs required a special ultraviolet light source and an EPROM programmer device to erase and reprogram them, whereas flash ROMs can be erased and rewritten without you even removing them from the system. On some systems, the flash ROM is not a separate chip but instead might be incorporated into the southbridge chip.

Using flash ROM enables you to load the upgrade into the flash ROM chip on the motherboard without removing and replacing the chip. Normally, these upgrades are downloaded from the manufacturer’s website. Depending on the design, some update programs require that you place the software on a bootable optical disc, whereas others configure the program to run on the next startup (before Windows loads), and still others actually run in Windows as a Windows application.

Some systems allow the flash ROM in a system to be locked (write-protected). In that case, you must disable the protection before performing an update—usually by means of a jumper or switch. Without the lock, any program that knows the correct instructions can rewrite the ROM in your system, which is not a comforting thought. Without the write-protection, virus programs could be written that overwrite or damage the ROM BIOS code in your system. The CIH virus (also called the Chernobyl virus) was one example that could overwrite the BIOS code on certain motherboards. Instead of a physical write-protect lock, some flash ROM BIOSs have a security algorithm that prevents unauthorized updates. This is the technique Intel uses on its motherboards, eliminating the need for a lock jumper or switch.

Note that motherboard manufacturers do not normally notify you when they upgrade the BIOS for a particular board. You must periodically log on to their websites to check for updates, which you can then download and install at no charge.

Before proceeding with a BIOS upgrade, you must locate and download the updated BIOS from your motherboard manufacturer. Log on to its website, and follow the menus to the BIOS updates page; then select and download the new BIOS for your motherboard.

Motherboard manufacturers may offer several ways to update the BIOS on a given motherboard, some may run directly from within Windows, and others might need to be run from bootable removable media such as optical or USB. You only need to use one, so if you have choices, in most cases you should choose the one that is the easiest to perform. Which one you choose can depend on the current state of the system. For example, if the BIOS is corrupt, you may have no other choice but to use the emergency recovery procedures shown in the next section. If the system you are updating is one you are building for the first time and does not yet have a working copy of Windows installed on the hard drive, you might want to use a method that works with other bootable media such as an optical drive or USB flash drive.

Most downloadable flash ROM upgrades fit into five main types:

  • Windows executable upgrades
  • BIOS Setup executable upgrades
  • Automated images of bootable media
  • User-created bootable media
  • Emergency recovery media

Top 12 PC Troubleshooting Problems and Solutions

These are some of the most frequently asked troubleshooting questions I receive, along with the solutions that typically address them.

When I power the system on, I see the power LED light and hear the fans spin, but nothing else ever happens.

The fact that the LEDs illuminate and fans spin indicates that the power supply is partially working, but that does not exclude it from being defective. This is a classic “dead” system, which can be caused by almost any defective hardware component. In my experiences I’ve had more problems with power supplies than most other components, so I recommend immediately using a multimeter to measure the outputs at the power supply connectors and ensure they are within the proper 5% tolerances of their rated voltages. Even if the voltage measurements check out, you should swap in a high-quality, high-power, known-good spare supply and retest. If that doesn’t solve the problem, you should revert to the bootstrap approach I mentioned earlier, which is to strip the system down to just the chassis/power supply, motherboard, CPU (with heatsink), one bank of RAM (one DIMM), and a video card and display. If the motherboard now starts, begin adding the components you removed one at a time, retesting after each change. If the symptoms remain, use a POST card (if you have one) to see whether the board is partially functional and where it stops. Also, try replacing the video card, RAM, CPU, and then finally the motherboard, and verify the CPU and (especially) the heatsink installation.

The system beeps when I turn it on, but there is nothing on the screen.

The beep indicates a failure detected by the ROM POST routines. Look up the beep code in the table corresponding to the ROM version in your motherboard. This can typically be found in the motherboard manual; however, you can also find the beep codes for the most popular AMI, Award, and PhoenixBIOS earlier in this chapter.

I see a STOP or STOP ERROR in Windows.

Many things, including corrupted files, viruses, incorrectly configured hardware, and failing hardware, can cause Windows STOP errors. See the section “Operating System Diagnostics” earlier in this chapter for more information on troubleshooting Windows error messages. One of the most valuable resources for handling any error message displayed by Windows is the Microsoft Knowledgebase (MSKB), an online compendium of articles covering all Microsoft products. You can visit the MSKB at, and from there you can use the search tool to retrieve information specific to your problem.

I see Fatal Exception errors in Windows 95/98/Me.

This is the equivalent of the STOP error in Windows NT or later. As indicated in the previous answer, this can be caused by both hardware and software problems, and the best place to check for specific solutions is in the Microsoft Knowledgebase (MSKB) at

The system won’t shut down in Windows.

This problem is usually caused by driver problems. (Try installing the latest chipset and power management drivers for your motherboard.) However, it can also be caused by bugs in motherboard ROM (try upgrading your motherboard ROM to the latest version), bugs in the various Windows versions (run Windows Update from Control Panel and install the latest fixes, patches, and service packs), or in some cases configuration or hardware problems.

The power button won’t turn off the system.

Desktop PCs built since 1996 mostly use the ATX form factor power supplies, which incorporate a design such that the Power Switch is connected to the motherboard and not the power supply directly. This enables the motherboard and operating system to control system shutdown, preventing an unexpected loss of power that can cause data loss or file system corruption. However, if the system experiences a problem and becomes frozen or locked up in some way, the motherboard might not respond to the power button, meaning it will not send a shutdown signal to the power supply. It might seem that you will have to pull the plug to power off the system, but fortunately a forced shutdown override is provided. Merely press and hold down the system power button (usually on the front of the chassis) for a minimum of 4 seconds, and the system should power off. The only drawback is that, because this type of shutdown is forced and under the control of the motherboard or operating system, unsaved data can be lost and some file system corruption can result. You should therefore run ScanDisk (Windows 2000 and earlier) or Chkdsk /F (Windows XP and later) from a command prompt to check for and correct any file-system issues after a forced shutdown.

I can’t connect to the Internet.

First, find out if any other computers or devices on your network can connect to the Internet. If not, check the broadband modem’s signal lights to see if you have a connection. If you do not have a connection, contact the ISP for help.

If you have a connection, unplug the router from AC power for about a minute and then plug it back in again. Computers with a wired connection will automatically reconnect. Wireless devices might reconnect automatically, or you might need to reconnect manually.

If only one device can’t connect, check the following. On a wired connection, make sure the Ethernet cable is plugged into working ports on the router or switch and the computer or device. Most Ethernet ports on computers have signal lights that flash to indicate a connection. If the signal lights are not flashing and the computer or device is turned on, the cable might be damaged. Test the cable and replace it if defective. If the connection is wireless, make sure the wireless radio is turned on. On many laptops, you can press a function-key or key combination or press a button on one side of the laptop to turn the wireless radio off and on. If the device uses a USB adapter, make sure it’s plugged in.

If you still can’t connect, run Windows troubleshooters for network and Internet connectivity. You can run these from Help and Support or from the Network and Sharing Center.

The keyboard doesn’t work.

The two primary ways to connect a keyboard to a PC are via the standard keyboard port (usually called a PS/2 port) and via USB. One problem is that some older systems that have USB ports cannot use a USB keyboard because USB support is provided by the operating system—for instance, if the motherboard has a USB port but does not include what is called USB Legacy Support in the BIOS. This support is specifically for USB keyboards (and mice) and was not common in systems until 1998 or later. Many systems that had such support in the BIOS still had problems with the implementation; in other words, they had bugs in the code that prevented the USB keyboard from working properly. If you are having problems with a USB keyboard, check to ensure that USB Legacy Support is enabled in the BIOS. If you are still having problems, make sure you have installed the latest BIOS and chipset drivers for your motherboard and any Windows updates from Microsoft. Some older systems never could properly use a USB keyboard, in which case you should change to a PS/2 keyboard instead. Some keyboards feature both USB and PS/2 interfaces, which offer the flexibility to connect to almost any system.

If the keyboard is having problems, the quickest way to verify whether it is the keyboard or the motherboard is to simply replace the keyboard with a known-good spare. In other words, borrow a working keyboard from another system and try it. If it still doesn’t work, the interface on the motherboard is most likely defective, which unfortunately means that the entire board must be replaced. If the spare keyboard works, then obviously the original keyboard was the problem.

I can’t hear sound from the speakers.

This can often be as simple as the speakers being unplugged, plugged into the wrong jacks, or powered off, so don’t overlook the obvious and check to be sure! Also check the volume controls in Windows or your application to see that they are turned up and not muted. When you are sure the volume is turned up, the speakers have power and are plugged in, and the speaker configuration is correctly identified in Windows (some audio hardware uses a proprietary mixer control for this job), you need to verify whether the problem is with the speakers or the sound card. To do this most efficiently, you merely connect different known-good speakers and see whether they work. If they don’t, clearly the issue is in the sound card—possibly the configuration of the card is incorrect or the card itself is defective. The first thing to try is clearing the ESCD in the BIOS Setup. This essentially forces the plug-and-play routines to reconfigure the system, which can resolve any conflicts. If this doesn’t help, try removing and reinstalling the sound card drivers. Finally, if that doesn’t help, physically remove and replace the card from the system. You might try replacing it first in the same slot and then in a different slot because timing issues can sometimes exist from one slot to the next. If that doesn’t work, you must try replacing the card. If the sound “card” really isn’t a card but is integrated into the motherboard, first try the ESCD reset and driver reinstallation. Then, if that doesn’t work, you have to try disabling the integrated sound and perhaps installing a replacement card or replacement motherboard.

If your problem is only with playing audio CDs, check for a cable between the sound card and the drive. If there is no cable, check the properties for the drive in the Device Manager in Windows to see whether the Digital CD Audio option is checked (enabled). If it’s not, enable it. If your system will not allow digital CD audio to be enabled, it is not supported and you must install an analog cable connected between the sound card and the drive.

The monitor appears completely garbled or unreadable.

A completely garbled screen is most often due to improper, incorrect, or unsupported settings for the refresh rate, resolution, or color depth. Using incorrect drivers can also cause this. To check the configuration of the card, the first step is to power on the system and verify whether you can see the POST or the system splash screen and enter the BIOS Setup. If the screen looks fine during the POST but goes crazy after Windows starts to load, the problem is almost certainly due to an incorrect setting or configuration of the card. To resolve this, open the special boot menu and select Windows Safe mode (hold down the F8 function key as Windows starts to load to display this menu).

This bypasses the current video driver and settings and places the system in the default VGA mode supported by the BIOS on the video card. When the Windows desktop appears, you can right-click the desktop, select Properties, and then either reconfigure the video settings or change drivers as necessary.

USB Security Risks

USB storage devices, such as flash memory “thumb” drives, have long been known to be a potential security risk. USB drives have been used to spread many types of malware, so it’s not surprising that blocking USB storage devices is a typical Group Security Policy setting in many corporate installations of Microsoft Windows. Most types of infections carried in the storage area of USB drives can be detected and removed with anti-malware software. Unfortunately, research announced at the July BlackHat 2014 security conference revealed that the security risks of USB go far beyond storage devices.

Security researchers Karsten Nohl and Jakob Lell of SR Labs discovered that the firmware in many types of USB devices, including flash drives, webcams, keyboards, and so on, can be rewritten to contain malware that cannot be detected with conventional anti-malware apps.

Their proof-of-concept malware, which they dubbed “BadUSB,” (see could be used to take over the connected device, use it as a relay point for data, enter commands as if they’re being typed by the user, and perform many other types of malware attacks. Once a system is infected with USB firmware-based malware, it can infect the next USB storage device connected to it—again, without conventional anti-malware (or even anti-rootkit) apps being able to detect the infection. Even if you use a Group Security Policy setting that blocks USB storage devices, a USB device’s firmware can be altered so that a USB flash drive, for example, appears as a different (non-blocked) USB class and can infect the target device.

The conclusion reached by SR Labs was sobering “As long as USB controllers are reprogrammable, USB peripherals should not be shared with others.”

To stop USB firmware attack vectors, a new generation of USB devices with unalterable firmware would need to be developed. Until this happens, there are precautions you can take to protect your information and devices:

  • Don’t use USB devices from untrusted sources on your computer—Maybe it’s time to stop grabbing “free” USB flash drives at conferences or trade shows.
  • Consider using other methods to distribute apps, utility programs, and updates—The venerable optical disc might be worth reviving as an alternative to the threat of USB infections.
  • Use cloud storage or optical drives instead of USB flash drives to receive client data.
  • Treat USB flash drives as “throwaways” if they are used to transfer data between trusted and untrusted devices.

How does a computers uninterruptible power supply work

What your computer expects to get from the power grid (in the United States) is 120-volt AC power oscillating at 60 Hertz (see How Power Distribution Grids Work for more information). A computer can tolerate slight differences from this specification, but a significant deviation will cause the computer’s power supply to fail. A UPS generally protects a computer against four different power problems:

  • Voltage surges and spikes – Times when the voltage on the line is greater than it should be
  • Voltage sags – Times when the voltage on the line is less than it should be
  • Total power failure – Times when a line goes down or a fuse blows somewhere on the grid or in the building
  • Frequency differences – Times when the power is oscillating at something other than 60 Hertz

There are two common systems in use today: standby UPS and continuous UPS. A standby UPS runs the computer off of the normal utility power until it detects a problem. At that point, it very quickly (in five milliseconds or less) turns on a power inverter and runs the computer off of the UPS’s battery (see How Batteries Work for more information). A power inverter simply turns the DC power delivered by the battery into 120-volt, 60-Hertz AC power.

In a continuous UPS, the computer is always running off of battery power and the battery is continuously being recharged. You could fairly easily build a continuous UPS yourself with a largish battery charger, a battery and a power inverter. The battery charger continuously produces DC power, which the inverter continuously turns back into 120-volt AC power. If the power fails, the battery provides power to the inverter. There is no switch-over time in a continuous UPS. This setup provides a very stable source of power.

Standby UPS systems are far more common for home or small-business use because they tend to cost about half as much as a continuous system. Continuous systems provide extremely clean, stable power, so they tend to be used in server rooms and mission critical applications.

How can I recover a deleted file from my computer recycling bin

If you delete a file and realize that you actually need it, you can recover it easily by doing the following:

  • Open the Recycle Bin by double-clicking on the Recycle Bin icon on your desktop (or you can go to the Recycle Bin folder in Windows Explorer).
  • Find the file you want to recover and click to highlight it.
  • Go to the File menu and choose the Restore option (or right click over the filename and select Restore from the context-sensitive menu).
  • The file is now back on your computer in its original place.

While the Recycle Bin is a great utility, there are times that a file is not placed in the Recycle Bin when you delete it. These include files from removable storage such as flash memory and Zip disks, files deleted from within some applications, and files deleted from the command prompt. Also, there are times that you will empty the Recycle Bin and then realize that there was a file you wanted to keep.

A common misconception is that the data is actually removed from the hard drive (erased) when you delete a file. Any time that a file is deleted on a hard drive, it is not erased. Instead, the tiny bit of information that points to the location of the file on the hard drive is erased. This pointer, along with other pointers for every folder and file on the hard drive, is saved in a section near the beginning of the hard drive and is used by the operating system to compile the directory tree structure. By erasing the pointer file, the actual file becomes invisible to the operating system. Eventually, the hard drive will write new data over the area where the old file is located.

There are several hard disk utilities that you can find on the Internet that allow you to recover “deleted” files. What these utilities do is search for data on the hard drive that does not have corresponding pointer information and present you with a list of these files. Your chances of fully recovering a file diminish the longer you wait after you deleted the file since the probability that the file has been overwritten increases. Sometimes you can recover portions of a file that has not been completely overwritten.

Troubleshooting PC Audio Problems

Although Plug and Play (PnP) PCI and PCIe sound cards and integrated audio have eliminated the troublesome hardware resource conflicts that once made adding audio to a PC a big headache, there are still many possible sources of frustration with recording or playback. In this excerpt from the 22nd edition of Scott Mueller’s Upgrading and Repairing PCs, Scott helps you troubleshoot your audio hardware.

Sound Card and Onboard Audio Problems

Like the common cold, sound hardware problems have common symptoms. Use the following sections to diagnose your problem.

No Sound

If you don’t hear anything from your computer, consider these solutions:

  • Are the speakers connected? Check that the speakers are plugged in to the sound card’s stereo line out or speaker jack (not the line in or microphone jack).
  • Are the speakers receiving power? Check that the power “brick” or power cord is plugged in securely and that the speakers are turned on.
  • Are the speakers stereo? Check that the plug inserted into the jack is a stereo plug, not mono.
  • Are the mixer settings correct? The mixer controls the volume settings for various sound devices, such as the microphone or the CD player. There might be separate controls for both recording and playback. Increase the master volume or speaker volume when you are in the play mode. With some audio hardware, you might need to use a proprietary mixer program (typically installed as part of the sound card or integrated audio setup) to have complete control of speakers, headphones, and microphones.
  • If the Mute option is selected in your sound mixer, you won’t hear anything. Depending on the speaker type and sound source type, you might need to switch from analog to digital sound for some types of sound output. Make sure that the correct digital audio volume controls are enabled in your audio device’s mixer control.
  • Use any setup or diagnostic software provided with your audio hardware or integrated sound to test and adjust the volume of the adapter. Such software usually includes sample sounds used to test the adapter.
  • Turn off your computer for 1 minute, and then turn it back on. A hard reset (as opposed to pressing the Reset button or pressing Ctrl+Alt+Delete) might clear the problem.
  • If your computer game lacks sound, check that it is designed to work with your audio adapter. For example, some legacy (DOS-based) and early Windows games might require Sound Blaster compatibility that modern versions of Windows no longer support. Refer to the section earlier in this chapter titled “Legacy Audio Support Through Virtualization.”
  • If you’re using motherboard-integrated audio, ensure that the onboard audio is enabled (check the BIOS Setup program) and that the proper drivers and player program have been installed (check the Windows Control Panel).
  • If you’re using motherboard-integrated audio that employs a removable header cable (such as with some SPDIF optical or four/six-channel analog speaker configurations), ensure that the header cable is properly connected to the motherboard.
  • Note that a few high-end cards have a connector for additional power; be sure to connect the appropriate power lead to ensure that the card will operate.

Volume Is Low

If you can barely hear your sound, try these solutions:

  • Are the speakers plugged into the proper jack? Speakers require a higher level of drive signal than headphones. Again, adjust the volume level in your mixer application.
  • Are the mixer settings too low? Again, adjust the volume level in your mixer.
  • Is the initial volume too low? If your audio adapter has an external volume control, check to ensure that it is not turned down too low.
  • Are the speakers too weak? Some speakers might need more power than your audio adapter can produce. Try other speakers, or put a stereo amplifier between your sound card and speakers.

Some Speakers Don’t Play

If you hear sound coming from some speakers, but not others, check the following:

  • Mono plug in the stereo jack—A common mistake is to use a mono plug in the sound card’s speaker or stereo out jack. Seen from the side, a stereo connector has two darker stripes. A mono connector has only one stripe.
  • No power to speakers—Check the AC adapter’s connection to the electrical outlet.
  • Loose speaker connection to some speakers—When possible, use keyed and color-coded connectors to avoid mistakes.
  • Speakers not set to same volume—Some speakers use separate volume controls on each speaker. Balance them for best results. Separate speaker volume controls can be an advantage if one speaker must be farther away from the user than the other.
  • Loose speaker jack—If you find that plugging in your speaker to the jack properly doesn’t produce sound but pulling the plug halfway out or “jimmying” it around in its hole can temporarily correct the problem, you’re on the road to a speaker jack failure. To avoid damage to the speaker jack, be sure you insert the plug straight in, not at an angle.
  • Incorrect sound mixer settings—Most systems assume that you are using two-channel (stereophonic) sound, even if you have plugged in four or more speakers. Select the correct speaker type with the Windows Speaker icon or a third-party sound mixer.
  • Additional speakers connected to the wrong jacks—Be sure you connect the additional speakers needed for four-channel, six-channel, or eight-channel audio to the correct jacks. If you connect them to line in or microphone jacks, they won’t work.
  • Incorrect balance settings—The volume control also adjusts the balance between the left and right speakers. If you hear audio from the left speakers only or the right speakers only, the balance control needs to be centered with the Windows Speaker icon or a third-party sound mixer.

Some Types of Sounds Play, But Others Don’t

If you can hear CDs but not WAV or MP3 digital music, or you can play WAV and MP3 but not CD or MIDI files, check the following:

  • Low volume or mute settings for some audio types—Some audio mixers have separate volume controls for WAV/MP3, MIDI, CD digital, CD audio, and other sound types and sources. Unmute any audio types you play back, and adjust the volume as desired. In Windows 7 and newer, you can set different volume levels for individual apps, such as Windows Media Player and YouTube. To do so, adjust the system volume to maximum, then adjust the volume control in each application as desired.

Scratchy Sound

Scratchy or static-filled sound can be caused by several problems. Improving the sound can be as simple as rearranging your hardware components. The following list suggests possible solutions to the problem of scratchy sound:

  • Interference from other cards—The sound card might be picking up electrical interference from other expansion cards inside the PC. Move the audio card to an expansion slot as far away as possible from other cards.
  • Dirty cable connector or jack—Unplug each connector and wipe it, and then reconnect it.
  • Interference from CRT display—The speakers can pick up electrical noise from your monitor. Move them farther away. Never place subwoofers near the monitor because their powerful magnets can interfere with the picture. Put them on the floor to maximize low-frequency transmission.
  • Some games don’t play at all or have poor-quality sound—If you notice sound problems such as stuttering voices, static, or a lack of audio on some games but not others, check with the game vendor for a software patch or with the sound card vendor for updated drivers. If you use Creative ALchemy for 3D audio, look up the settings for your game at the Creative Labs ALchemy website. If the game uses DirectX under Windows XP or older versions, run the DXDIAG diagnostics program from the Windows Run dialog. Click Start, click Run, typedxdiag, and click OK. (Windows Vista and newer versions also include DXDIAG, but they do not support hardware audio acceleration.) In DXDIAG, click the Sound tab. Adjust the slider for Hardware Sound Acceleration Level down one notch from Full (the default) to Standard, click Save All Information, and exit. Retry the game. If the problem persists, adjust the Hardware Sound Acceleration Level to Basic. If other games have performance problems after you adjust the Hardware Sound Acceleration Level, be sure to reset it to Full before playing those games.

Your Computer Won’t Start

If your computer won’t start at all after you installed a new sound card, you might not have inserted the sound card completely into its slot. Turn off the PC and then press firmly on the card until it is seated correctly.

If you can’t start your computer after installing a new sound card and its drivers, you can use the Windows “bootlog” feature to record every event during startup; this file records which hardware drivers are loaded during startup and indicates whether the file loaded successfully, didn’t load successfully, or froze the computer. See the documentation for your version of Windows for details on how to create a bootlog when necessary.

Advanced Features

If you are having problems playing DVD audio, playing MP3 files, or using SPDIF connections, make sure of the following:

  • You have enabled the hardware resources on the sound card.
  • You are using the correct playback program.
  • Your mixer has the correct volume control setting for the device.
  • You have enabled digital playback (if you are using coaxial or optical SPDIF output).
  • Your cabling is correct for the device.

Other Problems

A good way to solve problems of all types with PnP cards and integrated hardware, a PnP BIOS, and Windows is to use the Device Manager to remove the sound card or integrated audio, restart the system, and enable the card’s components to be redetected. This installs a “fresh” copy of the software and reinserts Registry entries.

If reinstalling the current driver with this method doesn’t improve your results, download and install updated drivers for your sound card or integrated audio.