PC Randomly Restarting

[KillerDark]

Hey guys, I just built a new PC and have been running into issues. Not sure if this is the right place to post or not. First off, here are my specs:

GPU: GeForce GTX 780 3GB
CPU: Intel Core i7-4770K Haswell 3.5GHz LGA 1150 84W Quad-Core
SSD: SAMSUNG 840 EVO MZ-7TE500BW 2.5" 500GB
Mobo: Gigabyte UD4H
Case: Fractal R4
Cooling: Cooler Master Hyper 212 EVO - CPU Cooler with 120 mm PWM Fan
Windows 8.1.

Reusing from my old PC (built around April 2010):

PSU: CORSAIR HX Series HX750 750W
RAM: 2x CORSAIR Vengeance 8GB 240-Pin DDR3 SDRAM DDR3 1600
HDD: Western Digital WD Green WD20EZRX 2TB IntelliPower 64MB Cache SATA 6.0Gb/s 3.5

I just put this PC together last Thursday/Friday and am running into an issue. My PC randomly restarts in the middle of playing Titanfall. I played the tutorial and 3 rounds last Friday night with no issue. Saturday I joined a game and it restarted within a few minutes. After it rebooted I played 2 matches and it rebooted in the middle of the 3rd. I ran RealTemp while playing TitanFall. Hottest my CPU got was 54C. My GPU was around 70ish. I have updated my BIOS and downloaded drivers for the mobo and gpu.

Last night I tried using just one stick of my memory, it restarted after a few matches. Next I tried using slots 2/4 (I had my memory in slots 1/3), it restarted after five or so matches. I then tried using different memory that I know has no issues (2x 4GB of http://www.newegg.com/Product/Product.aspx?Item=N82E16820231314)... it worked for 8 or 9 matches and I thought I had figured it out... but nope, restarted. CPU/GPU temps were about the same as I posted last time (Above). When it restarts its just in the middle of playing, screen goes black, power button LED goes off and then its rebooting. The only thing I see in the event log when this happens is:

The process Explorer.EXE has initiated the shutdown of computer JASON on behalf of user Jason\Jason for the following reason: Other (Planned)
Reason Code: 0x80000000
Shutdown Type: shutdown
Comment:

The process C:\Windows\system32\winlogon.exe (JASON) has initiated the shutdown of computer JASON on behalf of user Jason\Jason for the following reason: No title for this reason could be found
Reason Code: 0x500ff
Shutdown Type: shutdown
Comment:

Guess the next step is to try a new PSU..? If anyone has any advice or suggestions I would appreciate it.

 

[mfenn]

The fact that Windows is recording a shutdown event indicates to me that this is a software problem instead of a hardware problem. Try re-installing Windows from scratch, making sure to not download any viruses in the process.

 

[KillerDark]

I did some more digging in the system log and I found this:

The system has rebooted without cleanly shutting down first. This error could be caused if the system stopped responding, crashed, or lost power unexpectedly.

Says the source is Kernal-Power and EventId is 41.

Also found this: The previous system shutdown at 12:18:12 AM on ‎2/‎16/‎2014 was unexpected.

Those events aren't there every time but it definitely is there for some of the times it restarted.

 

[mfenn]

Ah OK, those are indeed unexpected reboot logs. Try downloading Furmark and Prime95 and running both at the same time. That'll send your PC to maximum power draw, way more than what any game will create. If your computer can run that for an hour without resetting, then you don't have a power issue.

 

[KillerDark]

Ah OK, those are indeed unexpected reboot logs. Try downloading Furmark and Prime95 and running both at the same time. That'll send your PC to maximum power draw, way more than what any game will create. If your computer can run that for an hour without resetting, then you don't have a power issue.

I ran those at the same time for an hour and didn't have any issues. CPU got up to 72C and GPU got to 76C. Not really sure where to go from here.

 

[mfenn]

At this point I would suspect the mobo. Is your machine new enough to get an RMA from the retailer?