New gaming PC build - Shuts down shorty after playing WoW

[misdirections]

I just finished building this computer today. All the parts are compatible, There is no problem with overheating as the CPU and Graphics card stay with 30-40 Celsius.

The system runs completely fine and without problems, up until I go and try to play a game. In this case WoW; Prior to this last shut down I lasted about 15 minutes playing before it shut off on me. This last time I lasted about an hour and a half.

Edit: When starting the computer back up after the shut down, The computer is Extremely slow once logged in. It is as if the computer had 250mb of RAM and then shortly after it freezes

I have performed a Memtest without any errors, As I Originally thought that as the problem. I have also performed a Burn In Test in hopes of finding any errors that way. But unfortunately nothing came up.
I have no clue as what the problem could be, Here is my system build.

http://pcpartpicker.com/user/misdirections/saved/YyG2FT

CPU
Intel Core i7-3820 3.6GHz Quad-Core Processor

CPU Cooler
Corsair H75 54.0 CFM Liquid CPU Cooler

Motherboard
Asus Sabertooth X79 ATX LGA2011 Motherboard

Video Card
Asus GeForce GTX 660 2GB Video Card

Memory
PNY XLR8 32GB (4 x 8GB) DDR3-1600 Memory

Storage
Seagate Barracuda 1TB 3.5" 7200RPM Internal Hard Drive

Case
Cooler Master Storm Scout 2 (Black) ATX Mid Tower Case
W/ Four 120mm Fans

Power Supply
Thermaltake Smart M 850W 80+ Bronze Certified Semi-Modular ATX Power Supply

Optical Drive
LG GH24NSB0 DVD/CD Writer

OS
Windows 8.1 - Fresh Install, There was no OS installed prior.

 

[meeshu]

I presume your system is not overclocked given relatively low CPU temperature?

I suspect a problem with your motherboard, in particular the chipset or VRMs may be overheating? But it may be that the PSU is faulty.

You could improve air flow through the computer by using appropriate fans. If this works (so there are no more shut downs) then this suggests the motherboard may be overheating and there might still be an underlying problem with the motherboard.

Although the Thermaltake PSU is of fairly good quality it may still be faulty. Another test is to try another good PSU if you can. If there are no more shut downs then the orginal PSU is faulty. If shut downs still occur then this suggests a motherboard problem. You may have to consider replacing the motherboard then.

 

[denis280]

Seagate Barracuda 1TB 3.5" 7200RPM Internal Hard Drive

start with testing this hdd with seatool

 

[Ketchup]

An i7 3820 will not stay within 30-40 Degrees Celsius under load. Put some load on the CPU and see what the temps are, just to rule that out.

 

[inachu]

This will sound like a stupid comment but also if your pc is on a power strip then also plug a desk light into the power strip.

Next time when the pc power resets and the light resets as well then it is not your pc but your home wiring.

 

[Firetrak]

Sounds like a GPU problem to me. Do you have another GPU laying around if so, plug that in and play wow then if it does not crash then thats your issue. If it does it'll be the CPU.

 

[DigDog]

*joke*

because it doesn't want to waste its life on such a low-spec game.