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Upgrading and Repairing PCs |
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Upgrading the BIOSIn this section, you learn how ROM BIOS upgrades can improve a system in many ways. You also learn why upgrades can be difficult and can require much more than plugging in a generic set of ROM chips. The ROM BIOS provides the crude brains that get your computer's components working together. A simple BIOS upgrade can often give your computer better performance and more features. The BIOS is the reason various operating systems can operate on virtually any PC-compatible system despite hardware differences. Because the drivers in the BIOS communicate with the hardware, the BIOS must be specific to the hardware and match it completely. As discussed earlier, instead of creating their own BIOS, many computer makers buy a BIOS from specialists such as American Megatrends, Inc. (AMI), Microid Research, or Phoenix Technologies Ltd. (for Phoenix and AwardBIOS). A motherboard manufacturer that wants to license a BIOS must undergo a lengthy process of working with the BIOS company to tailor the BIOS code to the hardware. This process is what makes upgrading a BIOS somewhat problematic; the BIOS usually resides on ROM chips on the motherboard and is specific to that motherboard model or revision. In other words, you must get your BIOS upgrades from your motherboard manufacturer or from a BIOS upgrade company that supports the motherboard you have, rather than directly from the BIOS developer. Often, in older systems, you must upgrade the BIOS to take advantage of some other upgrade. To install some of the larger and faster Integrated Drive Electronics (IDE) hard drives and LS-120 (120MB) floppy drives in older machines, for example, you might need a BIOS upgrade. Some of the machines you have might be equipped with older BIOS that do not support hard drives larger than 8GB, for example. The following list shows some of the primary functions of a ROM BIOS upgrade; the exact features and benefits of a particular BIOS upgrade depend on your system:
If you install newer hardware or software and follow all the instructions properly, but you can't get it to work, specific problems might exist with the BIOS that an upgrade can fix. This is especially true for newer operating systems. Many systems need to have a BIOS update to properly work with the Plug and Play features of Windows 9x, Me, XP, and 2000. Because these problems are random and vary from board to board, it pays to periodically check the board manufacturer's Web site to see whether any updates are posted and what problems they fix. Because new hardware and software that are not compatible with your system could cause it to fail, I recommend you check the BIOS upgrades available for your system before you install new hardware or software, particularly processors. You can use the BIOS Wizard utility available from eSupport.com (formerly Unicore) to test your BIOS for compatibility with popular BIOS features, such as Zip/LS-120 booting, ACPI power management, PCI IRQ routing, and more. Download it from www.esupport.com/techsupport/award/awardutils.htm. Where to Get Your BIOS UpdateFor most BIOS upgrades, you must contact the motherboard manufacturer by phone or download the upgrade from its Web site. The BIOS manufacturers do not offer BIOS upgrades because the BIOS in your motherboard did not actually come from them. In other words, although you think you have a Phoenix, AMI, or Award BIOS, you really don't! Instead, you have a custom version of one of these BIOS, which was licensed by your motherboard manufacturer and uniquely customized for its board. As such, you must get any BIOS upgrades from the motherboard or system manufacturer because they must be customized for your board or system as well. In the case of Phoenix or Award, another option might exist. A company called eSupport (formerly Unicore) specializes in providing Award BIOS upgrades. eSupport might be able to help you if you can't find your motherboard manufacturer or if it is out of business. Phoenix has a similar deal with Micro Firmware, a company it has licensed to provide various BIOS upgrades. If you have a Phoenix or an Award BIOS and your motherboard manufacturer can't help you, contact one of these companies for a possible solution. Microid Research (sold through eSupport, formerly Unicore) is another source of BIOS upgrades for a variety of older and otherwise obsolete boards. These upgrades are available for boards that originally came with AMI, Award, or Phoenix BIOS, and they add new features to older boards that have been abandoned by their original manufacturers. Contact eSupport for more information. Determining Your BIOS VersionWhen seeking a BIOS upgrade for a particular motherboard (or system), you need to know the following information:
You usually can identify the BIOS you have by watching the screen when the system is first powered up. It helps to turn on the monitor first because some take a few seconds to warm up and the BIOS information is often displayed for only a few seconds.
In addition, you often can find the BIOS ID information in the BIOS Setup screens. eSupport also offers a downloadable BIOS Agent that can be used to determine this information, as well as the motherboard chipset and Super I/O chip used by your motherboard. After you have this information, you should be able to contact the motherboard manufacturer to see whether a new BIOS is available for your system. If you go to the Web site, check to see whether a version exists that is newer than the one you have. If so, you can download it and install it in your system. Most BIOSs display version information onscreen when the system is first powered up. In some cases, the monitor takes too long to warm up, and you might miss this information because it is displayed for only a few seconds. Try turning on your monitor first, and then your system, which makes this information easier to see. You usually can press the Pause key on the keyboard when the BIOS ID information is being displayed, which freezes it so you can record the information. Pressing any other key allows the system startup to resume. Part of the PC 2001 standard published by Intel and Microsoft requires something called Fast POST to be supported. Fast POST means that the time it takes from turning on the power until the system starts booting from disk must be 12 seconds or less (for systems not using SCSI as the primary storage connection). This time limit includes the initialization of the keyboard, video card, and ATA bus. For systems containing adapters with onboard ROMs, an additional 4 seconds are allowed per ROM. Intel calls this feature Rapid BIOS Boot (RBB), and it is supported in all its motherboards from 2001 and beyond—some of which can begin booting from power-on in as little as 6 seconds. Backing Up Your BIOS's CMOS SettingsA motherboard BIOS upgrade usually wipes out the BIOS Setup settings in the CMOS RAM. Therefore, you should record these settings, especially the important ones such as hard disk parameters. Some software programs, such as the Norton Utilities, can save and restore CMOS settings, but unfortunately, these types of programs are often useless in a BIOS upgrade situation. This is because sometimes the new BIOS offers new settings or changes the positions of the stored data in the CMOS RAM, which means you don't want to do an exact restore. Also, with the variety of BIOS available, I have yet to find a CMOS RAM backup and restore program that works on more than just a few specific systems. You are better off manually recording your BIOS Setup parameters, or possibly connecting a printer to your system and using the Shift+Prtsc (Print Screen) function to print each of the setup screens. Turn on your printer, start your computer normally, and restart it without turning off the system to initialize the printer to try this option. Some shareware programs could print or even save and restore the BIOS Setup settings stored in the CMOS RAM, but these were BIOS version specific and would not work on any other system. Most of these programs were useful during the 286/386 era, but most systems released since—especially those with Plug and Play capabilities—have rendered most of these older programs useless.
Using a Flash BIOSVirtually all PCs built since 1996 include 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 even removing them from the system. On many recent systems, the flash ROM is not a separate chip but might be incorporated into the South Bridge chip. Using flash ROM enables you to download ROM upgrades from a Web site or receive them on disk; you then can 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 Web site, and then an included utility is used to create a bootable floppy with the new BIOS image and update program. It is important to run this procedure from a boot floppy so that no other software or drivers are in the way that might interfere with the update. This method saves time and money for both the system manufacturer and end user. Sometimes the flash ROM in a system is write-protected, and you must disable the protection before performing an update—usually by means of a jumper or switch that controls the lock on the ROM update. Without the lock, any program that knows the correct instructions can rewrite the ROM in your system—not a comforting thought. Without the write-protection, virus programs could be written that copy themselves directly into the ROM BIOS code in your system. Even without a physical write-protect lock, modern flash ROM BIOSs have a security algorithm that helps prevent unauthorized updates. This is the technique Intel uses on its motherboards. Note that motherboard manufacturers will not notify you when they upgrade the BIOS for a particular board. You must periodically log on to their Web sites to check for updates. Usually, any flash updates are free. Before proceeding with a BIOS upgrade, you first must locate and download the updated BIOS from your motherboard manufacturer. Consult the Vendor List on the DVD to find the Web site address or other contact information for your motherboard manufacturer. Log on to its Web site, and follow the menus to the BIOS updates page; then select and download the new BIOS for your motherboard.
The BIOS upgrade utility is contained in a self-extracting archive file that can initially be downloaded to your hard drive, but it must be extracted and copied to a floppy before the upgrade can proceed. Different motherboard manufacturers have slightly different procedures and programs to accomplish a flash ROM upgrade, so you should read the directions included with the update. I include instructions here for Intel motherboards because they are by far the most common. Intel and other typical flash BIOS upgrades fit on a bootable floppy disk; some recent BIOS upgrades from Intel and other vendors can also be run from within the Windows GUI. Older Intel and some other flash BIOS upgrades also provide the capability to save and verify the current BIOS version before replacing it with the new version and also provide the capability to install alternative languages for BIOS messages and the BIOS setup utility.
If the BIOS setup is performed with a bootable floppy disk, the first step in the upgrade after downloading the new BIOS file is to enter the CMOS Setup and write down or record your existing CMOS settings because they will be erased during the upgrade. Then, you create a DOS boot floppy and uncompress or extract the BIOS upgrade files to the floppy from the file you downloaded. Next, you reboot on the newly created upgrade disk and follow the menus for the actual reflash procedure. The iFlash procedure covered in this section is similar to the BIOS update process used by most non-Intel motherboards and must be used for systems running Windows 95, MS-DOS, or non-Windows operating systems such as Linux. Intel's Express BIOS update (for Windows 98, Windows NT 4, and current Windows versions) uses the InstallShield loader program familiar to Windows users to install BIOS upgrades within the Windows GUI. Here is a step-by-step procedure for the process using Intel's iFlash (DOS-based) BIOS update:
Flash BIOS RecoveryWhen you performed the flash reprogramming, you should have seen a warning message onscreen similar to the following: The BIOS is currently being updated. DO NOT REBOOT OR POWER DOWN until the update is completed (typically within three minutes)... If you fail to heed this warning or something interrupts the update procedure, you will be left with a system that has a corrupted BIOS. This means you will not be able to restart the system and redo the procedure, at least not easily. Depending on the motherboard, you might have to replace the flash ROM chip with one that was preprogrammed by the motherboard manufacturer or from a vendor such as BIOSWorld (www.biosworld.com), which provides replacement BIOS chips containing the same BIOS code as that provided by your motherboard vendor. This is an unfortunate necessity because your board will be nonfunctional until a valid ROM is present. This is why I still keep my trusty ROM burner around; it is very useful for those motherboards with socketed flash ROM chips. In minutes, I can use the ROM burner to reprogram the chip and reinstall it in the board. If you need a ROM programmer, I recommend Andromeda Research Labs (see the Vendor List on the DVD). In many of the latest systems, the flash ROM is soldered into the motherboard so it can't be replaced, rendering the reprogramming idea moot. However, this doesn't mean the only way out is a complete motherboard replacement. Most motherboards with soldered-in flash ROMs have a special BIOS Recovery procedure that can be performed. This hinges on a special non-erasable 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:
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.
Using IML System Partition BIOSIBM and Compaq used a scheme similar to a flash ROM, called Initial Microcode Load (IML), in some of their older Pentium and 486 systems. IML is a technique in which the BIOS code is installed on the hard disk in a special hidden-system partition and is loaded every time the system is powered up. Of course, the system still has a core BIOS on the motherboard, but all that BIOS does is locate and load updated BIOS code from the system partition. This technique enabled Compaq and IBM to distribute ROM updates on disk for installation in the system partition. The IML BIOS is loaded every time the system is reset or powered on. Along with the system BIOS code, the system partition contains a complete copy of the Setup and Diagnostics or Reference Disk, which provides the option of running the setup and system-configuration software at any time during a reboot operation. This option eliminates the need to boot from this disk to reconfigure the system and gives the impression that the entire Setup and Diagnostics or Reference Disk is contained in ROM. One drawback to this technique is that the BIOS code is installed on the hard disk; the system can't function properly without the correctly set-up hard disk connected. You can always boot from the Reference Disk floppy should the hard disk fail or become disconnected, but you can't boot from a standard floppy disk.
Motherboard CMOS RAM AddressesIn the original IBM AT system, a Motorola 146818 chip was used as the real-time clock (RTC) and CMOS RAM chip. This special chip had a simple digital clock that used 14 bytes of RAM and an additional 50 more bytes of leftover RAM in which you could store anything you wanted. The designers of the IBM AT used these extra 50 bytes to store the system configuration. Modern PC systems don't use the Motorola chip; instead, they incorporate the functions of this chip into the motherboard chipset (South Bridge) or Super I/O chip, or they use a special battery and NVRAM module from companies such as Dallas or Benchmarq. Table 5.6 shows the standard format of the information stored in the 64-byte standard CMOS RAM module. This information controls the configuration of the system and is read and written by the system setup program.
Note that many newer systems have extended CMOS RAM with 2KB, 4KB, or more. The extra room is used to store the Plug and Play information detailing the configuration of adapter cards and other options in the system. As such, no 100% compatible standard exists for how CMOS information is stored in all systems. You should consult the BIOS manufacturer for more information if you want the full details of how CMOS is stored because the CMOS configuration and Setup program typically are part of the BIOS. This is another example of how close the relationship is between the BIOS and the motherboard hardware. Backup programs and utilities are available in the public domain for CMOS RAM information, which can be useful for saving and later restoring a configuration. Unfortunately, these programs are BIOS specific and function only on a BIOS for which they are designed. As such, I don't usually rely on these programs because they are too motherboard and BIOS specific and will not work on all my systems seamlessly. Table 5.7 shows the values that might be stored by your system BIOS in a special CMOS byte called the diagnostic status byte. By examining this location with a diagnostics program, you can determine whether your system has set trouble codes, which indicate that a problem previously has occurred.
If the diagnostic status byte is any value other than 0, you typically get a CMOS configuration error on bootup. These types of errors can be cleared by rerunning the setup program. Replacing a BIOS ROMSystems dating from 1995 or earlier usually don't have a flash ROM and instead use an EPROM. To upgrade the BIOS in one of these systems, you replace the EPROM chip with a new one preloaded with the new BIOS. As with a flash ROM upgrade, you must get this from your motherboard manufacturer. There is usually a fee for this because the manufacturer must custom-burn a chip just for you and mail it out. Most boards older than 1995 are probably not worth upgrading the BIOS on, so weigh this option carefully! It doesn't make sense to spend $50 on a new BIOS for an ancient board when a new Pentium or Pentium II board can be had for $75, and that new board will include a flash BIOS and many other new features.
The procedure for replacing the BIOS chip is also useful if you have made a backup copy of your socketed system BIOS chip and need to replace a damaged original with the backup copy. To replace the BIOS chip, follow these steps:
As you can see, things are much easier with a modern motherboard with a flash ROM because you usually don't even have to remove the lid (unless the flash BIOS is write-protected as discussed earlier in this chapter). Year 2000 BIOS IssuesAll systems now in use should be compliant with twenty-first century dates, either through BIOS updates or through software or hardware patches. However, if you are returning stored systems built before 1999 to service, you might want to test them for year-2000 compliance. For details, see Upgrading and Repairing PCs, 12th Edition, available in electronic form on the DVD-ROM packaged with this book.
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