System shutting down suddenly, no BSOD

P-Stew

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Feb 22, 2007
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I built this system about 2 months ago, and until this week had not had any issues. Earlier this week I had the system suddenly shut down on me, almost as if it had lost power. I peeked inside the case window, and the mobo power button was illuminated (telling me there was indeed power -- at least at the time I was looking), so I hit the power button on the case, started the system back up, and all seemed well. Fast forward to today and the same thing happened twice within an hours span of time. At this point, I am thinking there is a short somewhere. Candidates are motherboard, psu, and maybe the case itself (short in the power button?) but I am hoping to narrow it down with some help/advice.

Specs are as follows:
Intel Core i7-4790K 4.0GHz (have not OC'd yet)
Gigabyte GA-Z97X-UD5H ATX LGA1150
G.Skill Ripjaws X Series 16GB DDR3-1600
Samsung 840 Pro Series 256GB 2.5" SSD
Windows 7 Home Premium
Gigabyte GeForce GTX 770 4GB
Corsair Professional 850W Power Supply

Before I start RMA'ing items I want to be fairly certain of what the problem is. Is there an obvious issue? I have built about a half dozen systems, so I know my way around for the most part, I just have not encountered this issue before. My leading candidate is the motherboard, but before I pull everything apart, I wanted to reach out here and see what you guys thought.

Edit: Forgot to mention what I was doing at the time of the crash. Two of the times, I was gaming while it happened. I have a Noctua U14S cooler in there and RealTemp has never shown the cpu above 62C even under heavy load (gaming + streaming baseball on a tv connected to the system + itunes + browsing). (Idles high 20s, low 30s -- also ambient house temp is between 73 and 77F) So maybe I have other candidates for issues.
 

P-Stew

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Feb 22, 2007
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Between the time I originally posted this and now, 11 days, the issue did not reoccur. It just happened again. I was gaming, system crashed and restarted after about 3 seconds. Windows did a disk check and when it finished booting, it crashed again. Started up after the same 3 seconds or so and then stayed on. I'm at a loss. Clearly the issue is intermittent if I went almost 2 weeks without anything happening.