Hello all, I've had issues for a while with my custom-build computer, but only recently have they become something more than minor.
OS: Windows 7, 64-Bit
Case: Cooler Master HAF X
Motherboard: Gigabyte GA-Z87X-UD3H
Processor: Intel i5-4670 (Haswell)
Video Card: AMD Radeon R9 280x 3GB
RAM: 16 GB (4x4 GB) Corsair Vengeance DDR3 1600 (CMZ8GX3M2A1600C9)
PSU: Corsair HX750 750W
Samsung 840 256 GB SSD (6 GB/s)
Seagate Barracude 2 TB HDD (6 GB/s)
Issues: The computer shuts off randomly (First noticed while gaming, very repeatable when gaming, but does not require gaming. Can happen when just web-browsing, or when the computer is idle just after starting up to the Windows login screen). Often times, after shutdown, the computer will not start back up (Hard-drive and fans spin up, but no POST codes, and the computer never displays anything on my monitor) I have done a clean install of Windows to make sure it was not software related, and have repeatedly checked my drivers.
I've disassembled the machine to ensure there was no short on the backside of the MOBO or from loose cables touching anything they shouldn't. I've made sure all cables were attached, and have removed and re-added the components to the MOBO to ensure proper seating and the like. The computer seems to run just fine. However, I installed Speccy today after reading about it on this forum, and I came across what I think may be the issue, though I am not sure.
This is the reading from the Voltage section of the Motherboard category in Speccy (Image also attached):