Built my first computer about 2 years ago and recently upgraded the processor and therefore had to get a new mobo. Installed the components and worked fine for about a week, then I started having random crashes some time during loading. I'm not terribly computer savvy so I did a little looking and convinced myself my hard drive was crashing. Replaced my 1.5TB Western Digital with a 2TB Western Digital 6.0GB which worked fine for the first day.

Yesterday I left the computer running over night trying to download some files I hadn't backed up. This morning it keeps crashing at start up before getting to the user log in screen. I pulled out the 2TB drive and put the 1.5TB back in. It booted up fine but wouldn't load anything except the background and task bar before freezing again. I switched back to the 2TB hard drive and on boot the system didn't register a hard drive was connected. I switched cords. SATA plugs, let it sit unplugged and same thing again and again.

Came to the conclusion that it isn't the hard drive, the plug, the cord and that the 1.5TB probably still works fine. Leaves with with the mobo it's self, the video card or the RAM. Any thought's would be extremely useful.

Mobo- ASRock 970 Extreme3
RAM- 4GB (2x2) Gskill
PSU- Corsair 750W
CPU- AMD Zambezi Quad Core 4.3gHz