Your computer's motherboard has a program called BIOS that runs when you first start up your computer. The software regulates the motherboard's function and allows you to launch your operating system. The process of updating your computer's BIOS, called flashing, is an advanced and risky process that should not be undertaken if not necessary for one reason: if something goes wrong, your computer will be left inoperable. In this case, you can either purchase a new motherboard or perform what is called a "Blind Flash."
Log on to the website of your motherboard manufacturer. Locate the file it offers for a "Recovery BIOS Update." You likely can find this section by searching for this phrase in the board maker's support section.
Copy the recovery file to a USB thumb drive. Make sure the file you copy has a .BIO extension.
Insert the thumb drive into one of the USB ports on the computer whose BIOS is corrupted.
Consult your motherboard's documentation to find where on the board the "BIOS Configuration Jumper" is located.
Unplug the computer's power cord.
Open your computer's case. Touch one of its metal side to ground yourself and dispel any static electricity on your fingers, then remove the BIOS Configuration Jumper from its documented location.
Plug the AC cord back in, then turn the computer on. You will see text scroll across your screen as the recovery executes itself. When the process is done, you will be prompted to turn off the computer, or it will turn off automatically.
Replace the BIOS Configuration Jumper on your motherboard after the computer has shut off. Close your case and reboot.