BIOS programs typically are stored in ROM (read-only memory) chips located on the motherboard because information stored in conventional RAM (random-access memory) disappears when you power off a computer. When you turn on your computer, the BIOS version number is often one of the first messages that appears on-screen. For example:

AMIBIOS (C)1992, American Megatrends, Inc. BIOS version 1.00.12.AX1T

Software developers frequently use and build upon data stored in the BIOS when designing programs. So, if the BIOS in your computer has a bug or lacks initialization code for a new peripheral, you may have to replace it. That's why a BIOS date and version number are so important.

A particular BIOS can significantly impact PC performance. Two hardware-identical machines might exhibit totally different personalities with different BIOS firmware (the software permanently stored in hardware chips). For example, in 1993, Gateway 2000 (a leading manufacturer and direct marketer of PC-compatible systems) confirmed that some of its local bus systems with a particular BIOS had problems running certain memory-resident applications. BIOS in these systems used an area of memory reserved for communication between applications. If users ran applications that occupied this part of memory, they were forced to reformat their hard drives. A corrected BIOS eventually was built into Gateway's newer models, and the problem disappeared.

In The Beginning

The collection of BIOS programs stored in ROM determines how your computer starts up. It performs the same set of routine operations every time. According to Mark Minasi in "The Complete PC Upgrade and Maintenance Guide," these steps are pretty much as follows: When you power on a computer, programming code in the main system BIOS determines which hardware is installed. The built-in program checks if this hardware is working. Then it searches for other BIOS-like programs installed on add-on boards in your system. If it recognizes any, it yields control of the system to those BIOS programs so that they can do their initial inventory and tests. When expansion board BIOSes have completed their startup routines, the main system BIOS continues with its tests, checking the computer's low memory and initializing those components it's designed to control.

Most of these operations occur very quickly, without users being aware of them. Sometimes, however, you do notice a particular stage in the BIOS POST (power-on self-test). For example, since a VGA controller adapter typically has its own BIOS chip, the software contained in video board ROM runs before the main system BIOS. As a result, you may notice a video board sign-on message before the main system BIOS copyright notice, date, and version number appear on-screen. When the main system BIOS tests low memory, a memory test message appears. When it inventories the hard drive, diskette drives, and keyboard, lights flash on those devices.

Once preliminary tests are complete and everything checks out, the BIOS pulls up additional information by loading the operating system into memory. It then reads a series of small boot files from the active drive (usually drive C:, the hard drive). Operating system software and boot applications take over from there.

The First Steps

When you purchase a computer, its BIOS firmware knows how to work intimately with your system's installed hardware components. To add new components (e.g., a large 1.2 gigabyte [GB] drive) to an older PC, you may have to upgrade your system BIOS so it can recognize drives with more than 1,024 cylinders. Computers manufactured in the early 1980s require a BIOS upgrade to use an EGA board, hard drive, local-area network card, or any ROM-equipped expansion board. Similarly, if you installed Windows 95 and want your computer to use the Plug-and-Play features of the operating system to manage installed peripherals or to recognize new peripherals that you add later, you must upgrade to a BIOS with built-in Plug-and-Play features.

Some BIOS upgrades require removal of the old BIOS chip from your motherboard and replacement with a new one. 80286, 80386, and 80486 machines typically have two BIOS chips rather than one. Pentium systems, on the other hand, store BIOS on a special kind of memory chip called flash RAM. With flash RAM, users don't have to replace any motherboard chips for a BIOS upgrade. They simply run a BIOS update program and let the software perform the modifications. While making these changes doesn't require much skill, an incorrectly installed flash BIOS will prevent the computer from starting up, so pay very close attention to update instructions that ship with the software.

In recent months, Gateway 2000 issued flash BIOS updates to integrate Plug-and-Play capabilities in its P5-75 through P5-100 systems and its P5-60 and 66 Rev 3 and 4 motherboards. The newest Gateway Pentium systems have Plug-and-Play BIOS revisions already installed. To add improved Plug-and-Play capabilities to a P5-90 system, for example, your system must have BIOS version 1.00.12.AX1T. In this article, we'll show you how to upgrade your flash BIOS for Plug-and-Play capabilities.

There are a couple of precautionary steps to take before you can safely update a system's flash BIOS. First, check with Gateway's technical support (800/846-2301) to inquire which BIOS version your computer should be running. You don't want to download or install the wrong BIOS. The technician will want to know which Pentium motherboard is installed in your computer. You'll find this information on the packing slip that shipped with your system.

Second, power on the computer and watch the screen for the message that tells you how to enter your computer's Setup program. On a machine with an AMI (American Megatrends Inc.) BIOS, you might have to press DELETE or F1 at startup. On a computer with a Phoenix BIOS, you may have to press CTRL-ALT-ESC. Other computers use different methods to access their Setup programs.

A built-in Setup program is that portion of your computer's BIOS that lets you determine several of your system's basic characteristics. It also tells the computer which type of diskette and hard drives are installed, the system bootup sequence (i.e., the drives the system checks when it looks for the operating system), serial and parallel port addresses, and more. This vital configuration information is stored in a special memory chip called CMOS (pronounced "see-moss"). Since CMOS memory is volatile, the chip must be connected to a working battery to retain information. If the battery fails, CMOS data dissolves, causing you to see either an "Invalid Configuration" or "CMOS Failure . . ." message at startup.

Since updating the BIOS might accidentally modify or erase working CMOS settings, make sure you run the Setup program and write down all CMOS information, noting the settings for equipment installed in your system. Alternatively, document your computer's CMOS by moving through each CMOS screen display and pressing PRINT SCREEN.

Issuing a Print Screen command from the keyboard outputs a hard copy of the computer's current screen display. This approach is more reliable than jotting down hand notes because it eliminates the possibility of user error. Be sure to print settings for both Standard (Main) and Advanced CMOS configurations. If a problem occurs later on, you can re-enter the Setup program and use the printout to reconfigure those settings.

Getting BIOS Update Files

If your computer doesn't have a modem, call Gateway's Customer Service (800/846-2073) to ask about obtaining a BIOS update on diskette. If your computer is equipped with a modem, you can get updated BIOS files by calling the Gateway 2000 Download Service (800/846-7562). Files may be downloaded free of charge, but you'll need to download the data onto a bootable, high-density system diskette. Depending upon the version number of the BIOS currently installed in your computer, you even may need to perform two BIOS updates. So, before you call the Gateway 2000 Bulletin Board System (BBS), prepare two bootable system diskettes in the following way:

1. Place the diskette you want to format in drive A:.

2. Double left-click Win95's My Computer icon.

3. When the window opens, left-click the icon labeled 3 1/2 Floppy [A:].

4. Choose Format from the File menu.

5. Select Full from Format Type, then check Copy System Files from the Other Options menu.

6. Left-click Start.

Repeat the procedure to format a second diskette. When you have two bootable diskettes, call the Gateway BBS.

To update via modem, follow these steps:

1. Use your modem to dial the Gateway BBS.

2.At the screen prompt, choose a language/ protocol (e.g., press 1 for English/ANSI, the standard English language version), then press ENTER.

3. Log in with the user ID guest.

4. Press L to access Gateway's driver library.

5. When the Driver File Download Library appears, choose 2 for Motherboard Utilities.

6.From the Motherboard Utilities menu, choose 5. . . Flash BIOS Updates For All Systems.

7. After the Flash BIOS Update Menu appears, choose the update for your particular system. For example, if you are running a P5-90 with a P54C Plato motherboard, select C . . . P5 (1.00.12.AX1T) BIOS to add Plug-and-Play capabilities in your main system BIOS.

(NOTE: If your current P5 BIOS version number is 1.00.09.AX1, you cannot update to 1.00.12.AX1T directly. First, upgrade your BIOS from 1.00.09.AX1 to 1.00.09.AX1T, then move up from 1.00.09.AX1T to 1.00.12.AX1T.)

Both procedures are essentially the same. For a two-stage BIOS update, follow these steps:

1.When the Flash BIOS Update Menu displays, choose B . . . P5-90 Flash BIOS (1.00.09.AX1T). A message appears stating that you'll be downloading a self-extracting file containing the BIOS update AX1T for P5-90 systems. This update will work only on systems with the BIOS revision 1.00.09.AX1 and prior .AX1 revisions. Once your system has been flashed with this version, it isn't possible to return to an earlier version.

2.You're now ready to download the first BIOS update. Verify download settings for your telecommunication program. Since you are going to download a file that could have adverse effects on your system if executed incorrectly, you want to ensure that your download directory is set correctly.

3.Choose a download option (e.g., Z for the Z Modem transfer protocol).

4.Press ENTER to begin the download process.

When you've finished downloading the 1.00.09AXIT update, you're ready to download the second file.

1. Choose C . . . P5 (1.00.12.AX1T) BIOS (updates for .AX1T BIOS only).

2. A notice tells you this file is an updated BIOS for the P5-75, 90, and 100 BIOS and that users must first upgrade to 1.00.09. AX1T before using this update. While you haven't yet upgraded to 1.00.09.AX1T, you have already downloaded the archived file, so you're all set.

3. Choose a download protocol (e.g., Z for Z Modem), then press ENTER to initiate the download process.

4. After the 12ax1t.exe transfer is complete, the computer returns to the Flash BIOS Updates menu. Press ALT-F4 to quit and disconnect. You also can type X, then press ENTER to exit. Repeat the X/Enter procedure three more times, then type Y in response to the flashing message that advises you are about to terminate your connection. Pressing Y automatically disconnects your modem from the Gateway BBS system.

Updating The BIOS

Each BIOS update transfers to your download directory as a self-extracting archive. To install these updates, proceed as follows:

1. Place the first bootable diskette in drive A:, then copy the P5ax1t.exe application to that diskette.

2.Double left-click drive A: to verify that a copy of the file now resides on the diskette. If you see an icon labeled P5ax1t.exe, you're ready for the next step.

3.Drag the original P5ax1t.exe archive file from the download directory on your hard drive to the Recycle Bin.

4.Right-click the Recycle Bin, then choose Empty Recycle Bin to delete its contents.

5.Return to drive A:, and make it active by left-clicking the drive A: icon.

6. Double left-click the P5ax1t.exe file icon in drive A:. The archive automatically self-extracts, copying its contents to the diskette. Scroll through the files to see what's there, making sure to read .TXT files for installation instructions.

7. Leave the diskette with the P5AX1T files in drive A:, then restart the computer.

8.Follow on-screen directions. After completing all steps, reboot once more, and a new BIOS copyright message will display on-screen.

You're now ready to perform the second BIOS update.

1. Place the second bootable diskette in drive A:.

2. Copy the 12ax1t.exe file from the download directory on your hard drive to the startup diskette.

3. Double left-click drive A: to verify there is a copy of the archived file. If you see an icon labeled 12ax1t.exe, you're ready for the next step.

4.Drag the original 12ax1t.exe archive file from the download directory to the Recycle Bin, then empty the bin to delete its contents.

5.Return to drive A:, and make it active by left-clicking the drive A: icon.

6.Expand the 12ax1t.exe archive as you previously expanded the P5ax1t.exe upgrade archive. Remember to print out and read the Readme.txt files for installation instructions.

When the computer restarts with the second bootable flash BIOS diskette in drive A:, the Flash Memory Update Utility screen appears. Press ENTER to continue and follow these steps:

1. After the Main Menu appears, use the down arrow key to highlight the option labeled Update Flash Memory Area From A File. Then press ENTER to continue.

2. When the Update Flash Area window appears, Update System BIOS should be highlighted. If it isn't, use the down arrow key to scroll to this option and highlight it. After it's highlighted, press ENTER.

3. When the Enter Path/Filename window appears, use the down arrow to highlight 1012ax1t_.bio in the Files box. Press ENTER.

4.When the Verify Image window appears, make sure that Continue With Programming is highlighted, then press ENTER.

5.Finally, after the "Continue" message appears, remove the bootable flash diskette from the diskette drive, then press ENTER. The system will reboot, displaying the message "BIOS Version 1.00.12.AX1T".

To ensure that the CMOS settings are still correct, enter the CMOS configuration setup at system startup, and check the settings against your printed copy. If there are any discrepancies, modify the settings to match the printout. Be sure to save changes when you exit.

Troubleshooting

If you inadvertently expand the archived BIOS upgrade files in the download directory, do NOT execute any BIOS program applications from your hard drive. If you do, you'll trash your computer's CMOS settings, which then must be reconfigured manually from the emergency printout you created earlier. In addition, you might trash a crucial operatin g system file, prompting a startup error message that reads "Bad or missing Sys file" or "Non-system disk". If this message appears, insert the Win95 Emergency Start Disk in your boot drive (drive A:), restart the computer, then type in the following command at the C> prompt:

sys a: c:

The SYS command transfers Io.sys and Msdos.sys (crucial DOS operating system files), as well as the Command.com file, to your hard drive without requiring reformatting. Once this transfer is complete, you can safely reboot. Everything should be back to normal.

by Carol S. Holzberg, Ph.D.