Tweak Your PC's BIOS Settings the Safe Way

If Windows is the happy face your computer projects to the world, then the BIOS is its dark, brooding subconscious. The BIOS--or Basic Input/Output System--is the code for fundamental PC functions, such as retrieving a keystroke from the keyboard or putting a pixel on the screen. This small program works behind the scenes, translating Windows' people-friendly commands into the zeroes and ones understood by your hardware. And like the human subconscious, the BIOS can have a powerful influence on your PC's behavior and performance.

BIOS Therapy

As new technology emerges and old bugs are discovered, computer makers often issue updated BIOS versions that can solve problems and improve performance. Check your PC maker's Web site for updates. But first, make sure you have the version number of your current BIOS; it usually flashes on your monitor right after you turn on your system. (Press the Pause key if it flashes too quickly.)

Updating your BIOS is easy, but you must do it with care. Usually you need only run a small program from a floppy disk. If a problem occurs, however, you can be left with a useless motherboard. So be sure to read all the instructions in the BIOS update's readme file beforehand. And always do exactly what the directions say.

If the BIOS is your PC's subconscious, then its Setup utility is the foundation on which you build your PC's character. The utility has user settings to control hard disks, memory, graphics cards, power saving, USB ports, and other hardware. The program used to come on a disk, but now it's conveniently stored in the same ROM chip as the PC's BIOS, enabling easy access. To open Setup, just press the key (or combination of keys) that you're prompted to enter when the PC starts up. Different BIOS makers use different keys--typically <Delete>, <F1>, or <F10>. Your screen should announce which key or keys to press for Setup just after it displays the BIOS version number. If it doesn't, check your system's documentation.

Because the Setup utility is made by the BIOS maker and is in the same chip as the BIOS, it's often called the BIOS Setup utility. And because it stores its settings in the clock/calendar chip--a complementary metal-oxide semiconductor, or CMOS, chip--it's also referred to as the CMOS Setup program. (The CMOS chip has its own battery to retain the chip's settings even when the PC is unplugged.)

The Setup utility has an abundance of hardware settings, ranging from the obvious, like one for the time on your PC's clock, to the arcane, such as the number of "wait states" that coordinate the flow of data between the RAM and the CPU.

First, Do No Harm

When working with your PC's Setup utility, use the same rule of thumb taught to budding brain surgeons: If you don't know what something does, don't mess with it. Inadvertently changing a wait state or other cryptic setting can slow performance or even cause a system crash.

If you think you may have accidentally changed a setting while working in the Setup utility, play it safe and start over. All Setup utilities have a menu choice that lets you exit without saving changes. You may also see a choice for returning the settings to their default values. Ignore this option: If your PC's vendor fine-tuned the system, the BIOS maker's default settings may not be optimal.

Back up your settings before making changes. When the battery that powers the clock/calendar chip dies, your settings die with it. If your Setup utility has a backup option, use it. If not, write your settings down on paper--or press the Print Screen key for each screen in the utility (this doesn't always work, however).

What to Look For

Before you start, read through the user manual that came with your PC or motherboard. Many manuals offer a short explanation of each setting. Settings vary by manufacturer and model, but you should find these on almost all PCs:

Optimization and compatibility settings: The Setup utility often contains settings for hardware performance. Sometimes these aren't set optimally at the factory, especially on generic or built-to-order PCs. Scan the entire Setup program. AGP mode settings and DMA settings are good candidates for optimization. These settings are also useful for troubleshooting newly installed hardware: Disabling or lowering a given setting may kick-start a heretofore incompatible graphics card, CD-ROM drive, or other device.

Hard-disk settings: You'll find a table, usually on a second or Advanced page and with "IDE" in its title, that lists all the configuration parameters for the EIDE hard drives directly connected to your motherboard. (SCSI hard drives and EIDE hard drives running off an expansion card will have their own configuration programs.) While most PCs made in the last few years can seamlessly detect and configure new hard disks, some require manual installation. Read your new disk's documentation on that procedure and use the on-screen options ( FIGURE 1 shows an example) to make changes in this table.

Floppy disk: This option lets you set the type of floppy drive (3.5-inch, 1.44MB, for instance) that you have designated as your A: or B: drive. This is a good setting to check if you're having floppy-drive problems. Some Setup utilities have a separate 'Floppy Read only' security setting that prevents your data from being written to a floppy disk and removed from the PC.

Boot sequence: This setting determines where the PC first looks for boot-up instructions. For example: 'A: then C:', 'C: then A:', or 'C:, Zip drive'. To boot from a CD-ROM, Zip, or LS-120 drive, you'll likely have to change this setting.

Password protection: If this is enabled, the BIOS will ask for a password before booting up. Be very careful with this one: If you forget the password, you'll have to reset a motherboard jumper or disconnect your CMOS battery, which will cause you to lose all your settings, or you may even have to buy a new motherboard.

IRQ settings: If you need an extra IRQ setting for new hardware, you may free one up by disabling an unused feature, such as a serial port, parallel port, or USB port.

Parallel port settings: Select the mode that works best for your hardware. ECP or EPP modes can speed up printers and other devices considerably (see FIGURE 2).

Fan RPM and CPU temperature: These two critical parameters should be checked periodically to ensure they are functioning properly.

Go Offline for Hardware Help

The Internet is great for finding answers to hardware questions, but sifting through Web sites looking for trustworthy advice can take a lot of time. (Unless, of course, you go straight to PCWorld.com.) Sometimes the fastest way to get answers is the old-fashioned way: with a good reference book. Here are two of the best.

Upgrading and Repairing PCs by Scott Mueller ($60) is the classic book covering everything you need to know about the PC and quite a bit you likely don't know. If you're looking for an all-around reference, this title's breadth and depth are unbeatable ( www.quepublishing.com).

PC Hardware in a Nutshell by Barbara Fritchman Thompson and Robert Bruce Thompson ($40) is a well-written, practical guide to buying and using PCs. It's loaded with real-world advice presented in a concise style that clearly delivers just the information you want, without your having to hunt for it ( www.oreilly.com).

Dirty Driving

A weekend remodeling job left a layer of dust over our whole office, and I'm worried that my CD-RW drive may be dirty. How should clean it?

Cory Hogan, Fresno, California

You probably shouldn't. The slightest smudge can block or jostle the drive's sensitive laser, so if it ain't broke, don't clean it. If your performance slows, or if your drive is unable to read the media, try a few well-directed blasts from a can of compressed air--available for less than $10 from computer stores (see FIGURE 3). Be sure to use the plastic straw that comes with the can. And keep the blasts short; extended rushes of air can cause condensation that deposits moisture on the drive's interior. Before using a CD-RW cleaning kit such as Kensington's $15 Drive Guardian, check with the drive maker; some recommend them, but others don't.

Brake for Old-Timers

Some really old software programs just don't work on today's high-speed PCs. If you have a golden oldie that locks up or spits out an error message every time you try to run it, give CPUKiller a try; it's a free, easy-to-use utility that lets you slow down your PC as little or as much as you want. Go to www.cpukiller.com to download your copy.

Click on the link for past Hardware Tips columns. Send your tips and questions to kirk_steers@pcworld.com. We pay $50 for published items. Kirk Steers is a PC World contributing editor.