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How BIOS Updates Are Performed

Two different ways of updating a motherboard BIOS are available.

With older systems, a physical chip swap (also called a BIOS chip upgrade) is necessary. The original BIOS chip is removed, and a new BIOS chip is inserted in its place. The new BIOS must be customized to match the old system's motherboard and chipset, use its existing CPU, and provide the enhanced features specified by the upgrade BIOS manufacturer. The typical cost range is around $60–90 for a single BIOS chip.

With newer systems that have a flash-upgradable BIOS, the update software is downloaded and installed onto a disk, which is used to boot the computer. Then, the new BIOS code is copied to the BIOS chip in a process that takes about 3–5 minutes. If the BIOS update comes from a source other than the original system or motherboard maker, it will also cost as much as $90 for the update.

In either case, the system might need to be reconfigured, especially if the new BIOS was physically installed, or if either a chip-based or flash-based BIOS is a different brand of BIOS than the original.

Where BIOS Updates Come From

The best (and cheapest!) place to get a BIOS update is from your motherboard or system vendor. Most major system manufacturers offer free BIOS updates for their systems with flash BIOS chips on their Web sites. For clone systems with motherboards from various producers, see the section "Determining Which BIOS You Have" later in this chapter.

A second source for BIOS updates is from one of the following companies.

For systems that originally used the Phoenix BIOS, contact Micro Firmware (http://www.firmware.com/ or 800-767-5465). Micro Firmware typically supplies updated Phoenix flash BIOS code on disk for systems they support. See the Web site for the current list of supported systems and motherboards.

For systems that originally used the Award, AMI, MR BIOS, or Phoenix BIOS (including systems not supported by Micro Firmware), contact Unicore Software (http://www.unicore.com/ or 800-800-BIOS). Unicore might supply the update on disk or as a replacement MR BIOS chip. Contact these vendors for details and prices, which vary by system.

Precautions to Take Before Updating a BIOS

Use the following checklist to be safe, not sorry, when updating a BIOS.

First, back up your data. An "almost working" BIOS that doesn't quite work with your hard drive can blow away your data.

Back up your current BIOS code if you can. Some BIOS update loader programs offer this option, but others don't. As an alternative, some BIOS chips keep a mini-BIOS onboard that can be reactivated in the event that a botched update destroys the main BIOS. Some motherboards have a jumper that can be used to switch to the backup; check your system documentation. For others, check the Micro Firmware Web site for its Flash BIOS Recovery Disks page to find out whether your motherboard is listed. If the BIOS update isn't completed properly, you could have a dead system that will need a trip to the manufacturer for repair. See the next section, "How to Recover from a Failed BIOS Update Procedure," for a typical recovery procedure.

Record your hard drive configuration information, including the following:

  • Cylinders

  • Heads

  • Sectors per Track

  • Translation (Normal, LBA [greater than 504MB], Large, and so on)

If you are switching to a different brand of BIOS, you might need to re-enter this information.

Record other non-standard BIOS settings, such as hard disk transfer rate settings, built-in serial and parallel port settings, and so on. A worksheet you can use as a guide is found later in this chapter.

Read carefully and completely the information provided with the flash BIOS download or chip-type BIOS update kit. Check online or call the BIOS manufacturer if you have any questions before you ruin your BIOS.

Check to see whether your system has a write-protect setting jumper on the motherboard that must be adjusted to allow a BIOS update to take place. Some motherboards disable BIOS updates by default to protect your system's BIOS from unauthorized changes. Set your motherboard to allow the change before you install the flash BIOS update, and reset the protection after the update is complete.

How to Recover from a Failed BIOS Update Procedure

Most motherboards with soldered-in flash ROMs have a special BIOS Recovery procedure that can be performed. This hinges on a special unerasable part of the flash ROM that is reserved for this purpose.

In the unlikely event that a flash upgrade is interrupted catastrophically, the BIOS might be left in an unusable state. Recovering from this condition requires the following steps. A minimum of a power supply, a speaker, and a floppy drive configured as drive A: should be attached to the motherboard for this procedure to work:

  1. Change the Flash Recovery jumper to the recovery mode position. Virtually all Intel motherboards and many third-party motherboards have a jumper or switch for BIOS recovery, which is normally labeled Recover/Normal.

  2. Install the bootable BIOS upgrade disk you previously created to perform the flash upgrade into drive A: and reboot the system.

  3. Because of the small amount of code available in the nonerasable flash boot block area, no video prompts are available to direct the procedure. In other words, you will see nothing onscreen. In fact, it is not even necessary for a video card to be connected for this procedure to work. The procedure can be monitored by listening to the speaker and looking at the floppy drive LED. When the system beeps and the floppy drive LED is lit, the system is copying the BIOS recovery code into the flash device.

  4. As soon as the drive LED goes off, the recovery should be complete. Power the system off.

  5. Change the flash recovery jumper back to the default position for normal operation.

When you power the system back on, the new BIOS should be installed and functional. However, you might want to leave the BIOS upgrade floppy in drive A: and check to see that the proper BIOS version was installed.


Note that this BIOS recovery procedure is often the fastest way to update a large number of machines, especially if you are performing other upgrades at the same time. This is how it is normally done in a system assembly or production environment.

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