System freeze (Hardware failure?)

[HawkAgent]

Recently I've upgraded few parts of my pc because my old mobo failed, my current specs are:

Asus P8P67 PRO B3 (new part)

Intel Core i7 2600K 3.4 GHz 8MB (new part)

G.Skill 8GB DDR3 (new part)

EVGA Geforce 8800 GTS Superclocked, 320 MB, GDDR3, PCI Express x16

Hitachi Deskstar T7K500, 320 GB, 7200 RPM, 16 MB, SATA II

Windows 7 64 bit @1920x1080

I have two displays connected to my GPU, my 24" monitor (connected via DVI) and my old tv (connected via TV-OUT). I have multiple display enabled on extended desktop mode, primary display is my monitor. One time, my parents downloaded some movie and were watch them on the secondary screen (the tv) and I was playing sims 3 (a videogame) on the monitor, both the monitor and tv went black, however the pc was still on, although I noticed the HDD LED on my system case was off and wasn't blinking anymore,as opposite of usual, on that time I assumed my GPU overheated or something, because I lost both signals to the displays.

Then the next day, also when my parents were watching a movie and I was playing the game, the computer suddenly froze, even the image froze, nothing moved. Also this time the HDD LED was off and stopped blinking. I find it weird because the first time it was clear my gpu failed because I lost video signals, but could it be my hard disk which is failing, or is it something else I'm overlooking?

I'm confused, I hope you guys can help me out.

[allen2]

Freeze like theese are often memory related. You should try testing your memory with memtest.

[HawkAgent]

Thanks for the reply. I tested my memory with memtest86+ twice, passed both without any errors.

[Tripredacus]

I am experiencing a similar issue with my PC locking up as you. Only rarely do I lose picture. I am not certain what my issue is, but I'm going to guess video card as well.

Do you run two different resolutions on both displays?

Does your video card support those heat/health monitor programs I've heard about?

[HawkAgent]

I'm running at 1920x1080 @60hz on my monitor, and 800x600 @29hz on my tv.

Not sure if my video card support those heat/health monitor programs, though I can try download and run them. I think it might be useful having a monitoring program log all events (like gpu core temp) when next freeze occurs. If you know any good programs I'd really appreciate it.

Also I just finished checking my harddisk for bad sectors with the windows diagnostic tool, no errors found.

[HawkAgent]

My screen went black suddenly while only surfing on the internet with firefox, also the HDD led went off. Could it be my video card?

[Tripredacus]

It could be. Do you have another one, or onboard to test?

Also make sure you check for updated drivers if you can.

Here is the link to the overclocking and temperature monitoring software for your video card

http://www.nvidia.com/object/nvidia_system_tools_6.06.html