I was having the dreaded Gigabyte boot loop. I found a very easy way to fix it. The problem is the CMOS gets somehow corrupted, and the computer can't even post. Using the CMOS clear jumper or removing the battery will sometimes work (if given enough time) but isn't reliable. The easy solution: Turn the computer off. Press and hold the power button. The computer will turn on. Keep holding and after about 5 seconds, the computer will turn off again. Power the computer back up. At this point it should run some type of check and determine the CMOS is corrupt. It will not post and will instead ask if you want to reload a stable BIOS into CMOS. You do, and then you should be up and running.