Ok so I built my first gaming PC last weekend but without the graphics card since it hadn't arrived yet. For the first 6 days the system was working absolutely perfectly with zero problems. Then, last thursday I installed the graphics card and it continued to work perfectly for one full day.
After that the computer randomly froze while I was surfing the web. No errors appeared on screen, the whole thing just locked up forcing me to turn off the system by holding the power button. I restarted the computer and after about ten minutes or so the same thing happened again.
This repeated a few more times forcing a hard shutdown each time. Eventually the computer wouldn't even finishing booting. It would either freeze at the Windows logo screen or it would freeze at the welcome screen after that. Sometimes the screen would just go blank and show only the mouse cursor which I could move for a couple of minutes before it would also freeze. I tried booting to safe mode and that would also freeze.
After trying recovery console and last known good configuration and booting to safe mode I gave up and reinstalled everything from scratch. After getting everything back up and running again including the graphics card and drivers things went smooth for about an hour before the same problems arose again.
So I reinstalled everything again minus the graphics card because I thought that was the problem. This time I ran a full chkdsk which took over 2 hours and found no problems so that eliminates the hard disk as the cause of the problem. Then I ran the windows memory diagnostics from the recovery console which turned up no problems so I don't think the RAM is the problem.
Before the problems ever started I had ran Prime 95 to test the CPU and it was fine. I also used Core Temp to monitor the temperature and it was normal. I ran Furmark to test the graphics card and that was also fine and there was never any visual glitches.
So anyway after eliminating the RAM, CPU and HDD as possible causes I was thinking it must have been the graphics card despite there having been no visual glitches of any kind. However just a while ago the system lock ups and now the refusal to boot have started again, this time without the graphics card installed.
This has led me to believe that the problem must be the motherboard and so I'm thinking I should try replacing it. I can't imagine what else could be causing these problems. Can somebody please help me?