Memory Or Motherboard Failure?

Fairly new built computer. Was working perfectly for about a month. The first symptom that something might have been wrong with it was the standby mode. At first, I'd hit the power button and it would come back from standby in less than a second. Suddenly the power button didn't work, and to get it to come back i'd have to hit the main power switch for a few seconds, and then it would Resume windows, however function slowly until a restart. Obviously when that started happening I disabled all the power saving features. Then suddenly one I come home from work, and I could do literally nothing without receiving an error message. So I ran the mem test that came with win7 and it passed. I formatted and re-installed the operating system and thought it a success when Old Republic fired up and ran perfectly, and still does. Every other game I've bothered it install, however, will give me a DLL error or a 0x00000005. So I made a memtest CD and ran that test. The results were....interesting. An attached photo explains it better... That's what happened after only 7 minutes of testing.

System is:
win7 professional 64
Gigabyte 990FXA-UD3
EVGA GTX560 Ti
G.SKILL Ripjaws Series 8GB (2 x 4GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800)

AMD FX 8120

OSZ GSX700 PSU (came form my last built, maybe not powerful enough?)

Please let me know if you need any more information.

 

I'm not using any wregistry cleaner software. only maintainance type software i'm using is avast antivirus. i'm under the impression that this is a pure hardware issue, but i'm leaning away from memory for a couple reasons. One, the fact that I need to disconnect my machine from power to get it to start back up from standby mode. Second, it didn't just fail a memtest, it produced a garbled screen. I've seen plenty of failed memory tests but never seen that.

 

Tried a couple more memtests. One with the "optimized defaults" enabled. That test stopped after only 45 seconds. The second with "fail-safe defaults" laster 8 minutes before I lost the picture. Just went black and my monitor went to sleep this time, rather than the garbled screen. Downloaded another game demo just for the laughs of it, which of coarse produces a unique missing .dll error of it's own when trying to launch it.

 

Would a GPU really overheat while running Memtest? Note, this has NEVER happened while playing a game. Only Memtest.

 

I updated the GPU firmware as you suggested, I also tried the BIOS update again. It has successfully completed an hour long memtest. I whipped my HD clean and and installing all my drivers again and we'll see if I still get those .dll errors or not. Standby issue are fixed too...

 

Yup fresh copy, but the FAQ for the firmware update said that the would stay with the card if installed in anothe machine. I'll double check to make sure I didn't misunderstand that. So far everything I've bothered to install is working. I still have to try Human Revolution. That was the only software, before, causing a full system crash.

Considering upgrading the cooling system of this entire thing. Even if it seemed sufficient, the stock fan on that 8-core is the loudest I've heard in over 5 years.