Im still thinking its a failing hard drive, Ive had this caviar HD for about 6 years It was the one I used to re-install win 7, Bc I wanted to avoid win 8 trying to boot in case my re-format didn't work. I do not remember placing a single win 8 file on this drive which is the perplexing thing why it came up in the first place. I couldn't even use my recovery file from the usb I had plugged in I made a recovery file as soon as I got win 7 to install. There MUST be some sort of shadow copy or something I missed on that hard drive. Started troubleshoot 1 stick ram, optical unit, same HD. gave me a 64 code. turned off tried different port first. back to 99 code, re-started about 3 times by itself HOLY SHIT I got bios!!!! What the hell?!? put in win 7 cd, said it was configuring win...... Win 7 just popped up with my new desktop background and all the zips I dled from asus sitting there?!? I did switch boot menu in BIOS to dvd first. So did I somehow screw something up in BIOS to where it only recognizes my OS on the dvd on boot? Hmmmm interesting apparently I traveled throught time as well the clock on the desktop says 11:20pm 12/31/2008 awesome.