I am not an experienced builder, but I've built 5 computers in the past few years. I built my most recent system five days ago with the following specs:
GIGABYTE GA-Z68X-UD3-B3 Mobo
Intel i7-2600K processor (not OC'd)
Thermaltake Black Widow 850W Power Supply
G.Skill Ripjaws X DDR3 1866 8GB (4GBx2)
MSI HD6670 1GB DDR5 Video Card
WD 1.5TB 7200rpm HD
Windows 7 Professional x64
I'm running AdAware PRO. I've installed MS Office 2010 and a few standard programs (WinRAR, Acrobat Reader) as well as all important updates through Windows Update.
Everything seemed to run fine for the first few days. Yesterday, the screen sudddenly turned solid light blue (not the BSOD color, but almost a sky blue). There was no writing on the screen and the mouse is not visible -- it's just a solid light blue color. Ctrl+Alt+Del has no effect. I have to use the reset button to force a reboot. After rebooting, the system seems normal and Windows has no record of any error (i.e., it doesn't say it recovered from an error, etc).
This has happened four times since yesterday. It appears to happen after the computer has been on for a few hours, but I can't figure out what's causing it. Two times it has happened while I've been using the system (running Win 7 with IE9 open), but two times it happened while the computer was idle. I've checked the temperatures on the CPU and graphics card at idle and under stress, but they are well within the normal range.
There are two other issues (that might be linked to the crashes?):
1) Even if I use XMP profiles, the Mobo refuses to recognize the memory as 1866. Instead, it only recognizes it as 1600 no matter what I seem to do. I've run Memtest86, which also recognizes the memory as 1600 and not 1866, but it finds no errors after several passes. Also, I've run the windows utility to scan the hard drive for any bad sectors, but it also finds no errors.
2) All four times, after forcing a reboot, all of my IE9 cookies and temporary internet files are gone. If I do a normal reboot, my IE9 cookies and temp files are retained, but after these blue screens, they are wiped out. Because this doesn't happen when I reboot normally (using Start menu -> Restart), I'm thinking this issue is linked to the system crashes.
I don't have any spare parts sitting around, so it's not easy for me to swap out a Mobo, memory, video card, etc. I suppose I could reinstall Win 7, but I figured I'd ask on here first to see if anyone has any ideas.
Since it is a new build I would run prime95 torture test on it for 24 hours and see what happens. While not all bsod errors are hardware - some are. You can try under clocking everything, and again running torture tests.
If torture testing rubs fine then its usually drivers and software. If it's hardware, power supplies can cause lots of instability and is usuallyworth swappingwith a spare if it's new.