
If you’ve just purchased a second hand laptop or computer from eBay or from a friend, you’d get VERY frustrated when you’re prompted to enter password before you can enter the BIOS when you don’t even know the password!
Even if you’re a computer technician, sometimes you need to access the BIOS to do some configuration. When you ask the customer for the BIOS password, and he’s like.. err… uh… he’s not sure what’s that.
BIOS is basic input output system. The set of routines stored in read-only memory that enable a computer to start the operating system and to communicate with the various devices in the system, such as disk drives, keyboard, monitor, printer, and communications ports.
Basically, if you plug in an IDE or SATA hard drive, sometimes you’ll need to access the BIOS to detect the hard drive. Well, nowadays it’s all auto detect. There’s also a whole lot of things you can configure in BIOS.
There are ways to reset the whole BIOS configurations by opening and short out pin your the motherboard, or can pull out the battery for a few minutes, and also there are some third party software that claims to reset or crack the BIOS password.
For Dell computers, there’s a Dell specific BIOS Boot Erase Disc to remove Dell’s computer BIOS ADMIN password.
This boot disc resets Dell BIOS to default erasing all admin and protection passwords saved by the BIOS.

I believe this disc is what DELL people uses to fix their own systems.
This file is in .iso format. ISO files are actually images of complete CDs compiles as one whole image, just like Ghost does for hard disks and partitions. ISO images can be loaded into several different CD recording software packages to create CDs.
To write ISO files to CD, if you have Nero, just launch Nero, select Open and locate the dellbiosboot.iso file. Enter a CD-R or CD-RW disc and click Burn.

[ Download Dell PC’s BIOS Boot Erase Disc (ISO) ]
Just a thought… I don’t think it’s possible to use this disc if the computer BIOS is password protected and the CD booting order sequence is disabled. In this case, you’ll have to use the old-school method that is opening and short out pin on your motherboard, or can pull out the battery for a few minutes.