The BIOS is the most basic instructions the computer uses. It tells the independent parts of the computer how to work together. If you load the wrong BIOS, it's kind of like me buying a book written in Chinese.
BIOS chips are replaceable. If the chip is soldered onto your motherboard, it is hardly worth replacing. If it is removable, then you have to find a new one (I did a quick look and didn't find one).