Hey vantorsen,
Sorry to hear you're still struggling. Have you considered trying to *underclock* your PC for a while, just to see if that improves stability/removes the corruption problems?
Your machine is exhibiting typical "instability" corruption problems, which can be caused by several things, including
1 buggy software,
2 buggy hardware,
3 overclocking or otherwise running hardware out of spec somehow, as well as
4 simple incompatibility between parts
5 broken/defective hardware
1 is a possibility, so try either stick with generic stuff that's known to work, or use the latest and hopefully most bugfree software available. This is particularly relevant w.r.t. motherboard/system & video drivers.
2 is fairly unlikely, and usually small hardware problems can be fixed with BIOS/driver updates anyway, so I don't think this is really your problem
3 Well you're not overclocking, and from what I can tell you're running everything at their rated speeds, so this should not be a problem. Might bet worth it to check all your kit for their rated specs (e.g. memory voltage again) and checking if everything checks out. This should include checking your PSU with a multimeter, including the video card PSU connectors. Also recheck and make sure that *all* the power cables are properly connected, including the CPU 12V rail and the 2x power connectors for the video card for those cards that have 2 (one is not enough, if it has 2, both need to be connected.)
4 From what I can tell there shoul be no incompatibility between your hardware. That said, if underclocking improves matters, that does suggest some sort of marginal incompatibility (since the components dont run stably at stock) hence why I asked if you've tried that.
5 This is always a possibilty, particularly if it's the RAM, but if so, then MemTest should find a problem. Running MemTest overnight is recommended. (I know you've run it for several hours already, suggesting that your RAM is fine, and by implication, your CPU, at least with respect to RAM intensive stuff.)
Anyway, good luck...