How to Overcome Your BIOS Fear

SAN FRANCISCO (03/20/2000) - Sure, you can tell a lot about people from the way they look. But to find out what makes 'em tick, you need to do some serious psychoanalysis. Your enigmatic PC is no different. Beneath its colorful screens and fancy pull-down menus lurks the BIOS--a bit of software that acts as the subconscious of your PC. And just as your subconscious controls your behavior, your PC's BIOS exerts a powerful influence on the machine's performance.

Here's what you need to know to gain the greatest insight into your PC's hidden psyche.

BIOS--short for Basic Input/Output System--is the low-level software that translates instructions and data from the language of the people-friendly commands Windows (or DOS, Linux, or whatever operating system you're running) uses into the cryptic language that controls the chips in your PC. Because the BIOS code resides in a chip that's located on your PC's motherboard, it's not easy to replace.

To properly govern the behavior of your computer's chips and devices--including hard drives, memory, parallel ports, and a great many others--the BIOS needs to know what types of devices your PC contains and (where you have a choice) how you want them to function. And it must have this information before loading the operating system. To make that possible, your PC stores the relevant settings on a separate memory chip known as CMOS (which stands for complementary metal-oxide semiconductor). The program used to access and change BIOS settings is called the CMOS Setup program.

This program has settings that both beginners and veterans will find useful.

You can do things as simple and obvious as adjusting the time and date maintained by your system or as complicated and obscure as altering the number of "wait states" your PC uses to coordinate the flow of data between the RAM and CPU. And since some settings here can override the corresponding settings in Windows--for example, to assign a specific IRQ to a serial port--the CMOS Setup program is the first place to look when you aren't able to resolve a hardware conflict in Windows.

Many PCs come with a motherboard manual that describes the PC's CMOS Setup program, setting by setting. If yours doesn't, check your PC manufacturer's Web site for documentation (sometimes PC makers customize the BIOS for their systems) and then the motherboard manufacturer's Web site.

Play it Safe

Changing CMOS settings can be useful--or dangerous. Resetting the time and date isn't hard; but if you select the wrong wait-state setting, for example, you may lock up your PC--a problem that can take many hours to fix. So use caution when working with the CMOS Setup program.

First, back up your CMOS settings--and not just as a safeguard against making unintended changes. When your PC is off, a battery on the motherboard constantly refreshes the CMOS settings. But when the battery dies--and they all do, eventually--so do the settings.

Some CMOS Setup programs come with a backup feature that writes your settings to a floppy. If yours does, use it. If not, try software that backs up CMOS settings; candidates include Norton Utilities and a number of shareware programs. But CMOS settings aren't standardized, so many of these programs--including Norton Utilities--only capture certain core settings common to all PCs.

Next, make a hard copy of your CMOS settings. If your PC is connected to a printer, try pressing the key to get a hard copy of each screenful of information in the CMOS Setup program. If that doesn't work, sharpen your pencil and start writing it all down.

Get with the Program

Accessing your computer's CMOS Setup program is easy; you just press a key (or key combination) when the PC starts up. Different BIOS makers use different keys--usually or , though Compaq PCs use . Your monitor screen should announce which key(s) to press. If it doesn't, check your PC's documentation.

Once you reach the CMOS Setup program, you need to Figure out how to get safely out of it. The main screen will list a number of submenus--like Standard, Advanced, Security, and Power Management--as well as the program's exit options. Be sure to find the Exit Without Saving Changes option (or its equivalent). It's your escape route if you ever suspect that you've altered a setting that you didn't mean to change.

You may also notice one or two menu choices that allow you to restore CMOS settings to their default values. Before using one of these, check your documentation to determine which choice restores what. One option--labeled something like 'Restore BIOS Default'--may return CMOS settings to a minimal configuration for troubleshooting purposes, an arrangement that sacrifices performance in favor of compatibility. Meanwhile, the other choice--possibly labeled 'Load Setup Default'--may restore settings to the optimal performance-oriented values they were given at the factory.

Following are just a few of the CMOS settings that you may find useful. The precise names given below may not match the settings in your BIOS--in fact, some may not even be offered in your setup program--but you should be able to find their equivalents without much difficulty. As a rule of thumb, if you don't know what a setting does, don't play with it. But if you're a diehard tinkerer who can't resist the temptation to squeeze a little more speed out of your computer, you should consult Phil Croucher's excellent book, The BIOS Companion, before playing with the values for any of the more arcane memory or chip set defaults.

Hard Disk Settings: This table of settings, which in most cases is located under the Standard menu selection, holds the configuration parameters that your PC needs to recognize your hard disk. The hard disk settings table can record data for up to four drives, one for each of the four EIDE devices supported by most motherboards.

You can enter the hard disk parameters manually, but almost all PCs made in the last few years come with a hard-disk auto-detection program that reads and enters the proper configuration data into CMOS. If you like, you can run the program manually from the CMOS Setup program.

Floppy Disk: This option lets you select the type of floppy drive (for instance, one designed for 3.5-inch, 1.44MB floppies) that you have in your A: and B: drives. Check this setting if you find yourself running into floppy drive problems. Some BIOS versions have a separate Floppy Read only setting that prevents data from being written to a floppy disk.

Boot Sequence: This setting determines the order in which the PC examines the drives for boot-up instructions. For example, it may begin with A: and go to C:. Or it may go from C: to the Zip drive, or from C: to A:. If you want to boot your machine from a CD-ROM, Zip, or LS-120 drive, you'll likely have to change this setting.

Password Protection: You can set the BIOS to ask for a password before you boot up, but be careful with this one. If you forget the password, you may have to reset a motherboard jumper, disconnect your CMOS battery (and lose all your settings), or even buy a new motherboard. (In some cases, your system manufacturer may be able to provide you with a "back door" password to use in an emergency--if you can prove that you're the owner.)Serial Port Settings: These are great places to investigate if you're having trouble installing a modem. Fixed IRQ and COM settings can wreak havoc on Windows and plug-and-play installations. For their part, serial ports may be turned on or off; so a serial port that seems dead may just be set to "disabled" in CMOS.

Parallel Port Settings: The preceding serial port tips apply here, too. But these settings also let you select which mode--standard, bidirectional, ECP, or EPP--the parallel port uses, and they determine the speed and transmission capabilities of the parallel-port connection. Most printers manufactured three or more years ago use the slower, standard mode. Many new, full-featured printers won't function without ECP connections. Printer problems can often be traced to a parallel port with the wrong mode setting.

Fan RPM and CPU Temperature: You can find the correct values for both of these critical parameters in the CMOS Setup program. Check the settings here periodically to ensure they are accurate.

The Ghost in the Machine

Every time I start my PC I get a 'Modem Not Ready' error message from my old ISP's software. I have a new ISP, a new modem, and I thought I deleted the old software. Is my PC haunted?

Helen Fairbairn, Eugene, Oregon

It sounds more like secreted software than pesky poltergeists. If you deleted the software without uninstalling it, you may have missed something. To track it down, select Start*Run, type msconfig, and press . Then select the Startup tab. You'll see a list of all the software that automatically loads when your system starts. If you don't recognize the offending program at once, begin disabling programs one by one--by unchecking the associated box--and restarting the system after each effort. When the error message goes away, you've found the culprit.

For additional hardware tips, see Send your questions and tips to We pay $50 for published items.

Kirk Steers is a PC World contributing editor.

Extra tip for 1805 HH/Hardware

Build a Better BIOS

Like all software, your PC's BIOS is updated continually, to correct newly detected bugs and to add new functionality.

Check your PC manufacturer's Web site to see whether an updated BIOS is available for your system. An updateable BIOS is also known as a Flash BIOS.

But first you'll need to know the version number of your current BIOS.

The version number is usually a long string of digits and letters. It flashes quickly at the top of your screen during the first moments of the boot process.

If it disappears too quickly, hit the Pause key to freeze the screen.

Updating your BIOS is like doing yard work around poison ivy: You should have a good reason for doing it, and is actually quite easy: Just download the file, read the instructions in the readme file, and follow them carefully. This usually entails running a small program from a floppy disk. Granted, problems are rare. But if they do occur, you can be left with a useless motherboard.

Faster Than a Speeding Finger

Can you scroll faster than you can talk? No? Maybe your keyboard's holding you back. To speed things up a bit, open Control Panel and double-click the Keyboard icon. Under the Speed tab, you'll find a sliding bar labeled 'Repeat rate' that's designed to set the speed of character repeats. Move the slider all the way to the right, to the side labeled 'Fast'. It won't make your fingers move faster, but you'll probably notice a big performance difference when you use the arrow keys to scroll through large text documents.

Norton Utilities

Street price: $50; Symantec; 800/745-6054; Info No. 608The BIOS CompanionStreet price: $25; Electrocution TechnicalSupport Services; 403/938-9979;

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