Troubleshooting Windows XP
The x86 Bios
The BIOS is built-in software which is typically placed in the ROM chip of your computer. On a PC, the BIOS contains the codes required to control such things such as your keyboard, disk drivers and communication ports. The BIOS also loads the operating system of your computer. You will need to enter the BIOS in order to change/verify low level system settings.
Entering the BIOS
Some people do not know how to enter their computer's BIOS because it holds such low-level functions, and is hardly something that is intuitive and is, in fact, different from computer to computer. The easiest way to learn how to enter your computer's BIOS is to restart your computer and look very carefully at your computer's Boot/Splash screen when it first starts up. There is usually directions on this screen to enter to BIOS -- look for something to the effect of, "Press Esc to enter Setup" -- here Esc is how you enter to BIOS. You must be quick; as soon as this screen passes you have lost your opportunity. If you cannot find instructions on this screen you will need to consult your user manual.
Alas, another reason people do not know how to enter the BIOS is that many manufacturers (cough...COMPAQ...cough) do not include the procedure for doing so in any of their manuals or on the splash screen. If the user of one of these computers wants to learn how to enter the BIOS they must surf the internet to the manufacturer's web site and browse message boards and troubleshooting articles to learn the appropriate key combinations.
Popular keys to enter the BIOS are: Delete, F2, F8, or ESC.
Here are a few important settings that can be found in your BIOS:
The reason your computer knows the date and time every time your computer starts up is because the memory that keeps track of it is kept active in your computer after it restarts. To set you date and time if it is shown incorrectly you will need to enter your BIOS and change it here.
When your computer starts up it looks at devices to see if they contain system software (such as DOS, Windows, or Linux). You may have noticed that when your computer starts the lights on your floppy drive or CD may flash -- this indicates that your computer is looking at them -- before it loads into your OS. The reason why it looks at these devices is because your the settings in your BIOS tell your computer to do so. In your BIOS you could change these settings so that it always looks at your hard drive first (improved boot time and better for security -- someone cannot bypass your Windows password by booting with a floppy), or to look at your hard drive last (improved machine flexibility).
Currently, most proprietary machines have many built in peripherals such as a sound, video, NIC, or controller cards. At some point in time you may wish to upgrade these components. In order to conserve system resources, and to avoid potential conflicts you will have to disable those devices in your BIOS.
IDE Drive Configuration
Not only do your IDE devices have to have their jumpers manually configured, but they also need to configured correctly inside your BIOS, otherwise your OS will never be able to see them. There are a variety of ways for these settings to be configured in order for the drives to work properly. The easiest strategy to ensure that your drives are working is to just have each device controller automatically detect the device settings on startup every time the computer starts. This will work, and is often the way most manufactured computers are set up, but this auto detection makes your boot last longer than is necessary. The easiest thing to do is manually auto detect the drive once in your BIOS and copy those settings to your device configurations -- most computer's BIOS makes this easy by providing an automated tool to accomplish this (the IDE HDD AUTO DETECTION option in the above picture).
If you value your computer's security you will want to set a BIOS password, you especially want to do this if you have changed the boot order to prevent people from booting from other devices.
When in Doubt
Most computer's BIOS have a feature to reset all settings to factory defaults. If you are having problems that you believe might lie in the BIOS, you can always reset you BIOS and restart the computer. These factory defaults are usually the safest, but slowest, settings your computer has. If your BIOS does not have this feature you can always remove your CMOS battery -- it will reset the settings just as when we replaced the battery on the previous page.