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BIOS Settings (CMOS Memory) Backup

There is an essential set of information that is critical to the operation of your PC, but is not stored on your hard disk at all. It is your BIOS settings, the group of parameters that controls critical aspects of how your PC works These settings are very important because minor changes to them can have a major impact on how your system functions. It can take a long time to "tweak" your BIOS settings to reach the set that allows your system to function at peak performance.

The BIOS settings for your PC are not stored in the system memory or hard disk. Instead, they are stored in a special reserved memory area that is commonly called the "CMOS Memory". A battery provides backup so that the settings are not lost when the PC is turned off or unplugged. Unfortunately, certain situations can cause the CMOS memory to be erased or settings lost; usually this can happen when the battery fails due to some sort of malfunction, or merely because the motherboard is getting old.

It makes sense therefore to back up the information in the CMOS memory on occasion. Under normal circumstances, the battery will last for quite a while, and most regular PCs keep their BIOS settings intact for years at a time. This means that the CMOS does not need to be backed up at nearly the frequency that regular data does. In fact, once you have created your initial backup (which you should do when you set up your PC), all you need to do is change the backup whenever you change the settings themselves, to make sure the backup is current.

Since the data is not on the hard disk, you can't just back this information up the way you would a regular file. There are in fact two different ways that the CMOS memory is normally backed up:

• Manual Backup: Take a piece of paper and your favorite writing implement. Go through the BIOS setup screens and record the settings and what their values are. It sounds tedious, but it is simple, foolproof (basically :^) ) and while it takes a while to do the first time, this is something you only do once when you set up a new PC, or change the motherboard. When you change your BIOS settings, you just change what is written on the piece of paper as well.

Tip: I have heard that it is possible with some BIOSes to get the BIOS setup screens to print out on the printer. Turn on the PC, and boot up DOS. Then hit {Ctrl}+{Alt}+{Delete} to reset the PC, and go into BIOS setup. On some systems, the routine that handles the {Print Screen} key will still function, and you can use it on each of the BIOS screens as a nifty shortcut! It won't work on all systems, and it won't work when you first cold start the PC, since the Print Screen handler hasn't been installed yet at all.

• CMOS Backup Utilities: There are small utilities that will go through the CMOS settings and record them to a regular file, which can then be backed up through normal means, or just copied to a couple of floppy disks. Some of these programs also offer the option of restoring the CMOS settings from one of these files if the CMOS ever gets wiped out. I don't know much about these programs; I would say that especially when it comes to any program that sets large numbers of CMOS settings: be careful...

Next: How To Back Up

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