System Randomly Shuts Off - Since Yesterday [Problem Details Within]

What's wrong?

Update:

System shut-downs are still happening - the last two occurred whilst playing a game (Borderlands).

I delved back into my computer case and removed and reseated my graphics card (completely cleared it of dust while it was out). However shut-downs are still occurring mid game play.

I happened to have temp monitoring software running when the shut downs happened. My CPU temp was 45-51°C and my GPU was at 67 -71°C on both occasions. These temps are well within safe operating limits.

Just ran the 15 minute burn in stress testing option featured in the benchmarking software Furmark 10.2; was at around 95% complete when I witnessed my system shut down - the GPU temp at the time was 89°C. Now when I immediately try to boot my computer up it is shutting itself immediately back down. This is making me believe that my issue is temperature related as my system is still too hot from the benchmark, it's likely shutting itself straight back off to prevent damage?

As my CPU and GPU temps are healthy under idle and load with gaming, maybe my issue is related to a part of my motherboard overheating? After some time passed, I could boot into Windows. My MCP (Southbridge) is running at 77°C and my SPP (Northbridge) is at 60°C, both currently at idle.

Any thoughts, anyone?

Sorry for leaving you hanging but...

Here's an update:

With my experience I had a hunch it was more likely hardware related as noted in one of my posts. I've gotten in touch with EVGA support (manufacturers of my motherboard) and preliminary steps have diagnosed my issue as to my motherboard becoming faulty. It's getting shipped off to them on Monday.

I'll post back here in a week or so if they confirm the fault at their end once they receive it. Here's hoping it was sorely to a faulty motherboard and my replacement is solid!

Well I regret to inform you all that the geniuses at EVGA Europe sent me out a faulty replacement motherboard. I'm currently in the process of getting them to allocate a UPS consignment for pick up which is taking longer than it should. (I was given the wrong tracking ID to schedule a pick up with - obscene level of support, I know)

They told me they only ship pre-tested boards and this shouldn't have happened, this is a lie, or at least in my case as the board was clearly not thoroughly tested and in worse condition than my original.

Support were polite however their grammar was all over the shop, even substituting the word 'you' with 'u'. A lot of sentences didn't make sense and required some effort to completely understand.

After the questioning the quality of their products and level of customer service I have decided to never again purchase a product from them. I'd highly recommend you follow suit if you want to avoid being unable to use a fully functional computer for nearly 4 months. (and still waiting).

EVGA, you've been named and shamed.

Final update: My second replacement motherboard (though horribly yellowed which had left over thermal paste smeared about) seems to be working after a weeks heavy usage. So my issue was definitely sorely due to a faulty Motherboard. I'll update my first post in this thread with this info.

Thanks again for your time and assistance karlsnooks.

Hope this assists with anyone having similar issue, and don't forget kids, stay the hell away from EVGA products. That is all! :)