Have you run memtest to ensure there's no errors in your memory chips? I've had that issue before but it caused bluescreens not lockups. And see if you've got another computer with a video card in it or a friend with an old video card lying around to test it with. run it until the normal time it would approximately crash.
all your voltages are fine cept the +5 VCCH but for some reason mine hangs in the 3's too and I have a powermax 850w PSU lol (think it's powermax brand, I know it's black lol) and if you test the ram and it passes, and you test another video card and it passes, then we know it's your video card, if it crashes with another GPU in I'd RMA the motherboard and get a replacement. It's the process of elimination really. Memory, video, power, cpu. and I'd say HDD error checking if ya haven't. But I'd assume that would lead to corrupted files rather then system lockups. Never had a HDD fail on me though.
sucks that our times we get online are offset lol would be nice to be able to talk abuot it in close to real time lol.
In other news, I found some generic DDR2 800 ram modules from a ghetto 600 dollar Acer desktop PC. slapped em in my computer for some extra ram, and they're running great at 4-4-4-4-10-16 1T and only underclocked them by 67mhz. Just goes to show even the noname generic stuff can work good too..it's all about luck lol.
Lemme get ya a couple links for software to run.
Everest Ultimate(30 day trial) very clean software, features a burn-in test among others. I'd say run it on the components it lists individually for atleast 30 minutes a piece or however long it normally takes for your computer to die. see if you can single one out that locks up.
http://tinyurl.com/lf4mbs <- that's a tinyurl version of the download from softpedia cause their link was HUGE lol.
ATItool (freeware) also clean software(while we're at it let's just assume everything I link is clean) This is a video card overclocking and testing tool. And don't worry it works for nvidia cards too despite the name. Edit: btw just press scan for artifacts, and it'll work your card really hard with that furry cube lol.
http://www.techpowerup.com/atitool/Memtest86 (freeware) the best memory diagnostic tool there is. burn the cd, boot it, run it.
http://www.memtest.org/download/2.11/memtest86+-2.11.iso.zipAs for opening the system crash dump hmmm...go here.
http://www.brighthub.com/computing/windows-platform/articles/29860.aspxIt's an article that tells you exactly what to do/get from microsoft to be able to analyze the dump(<- lol)
I wish ya the best of luck, i sincerely HATE computer problems lol I hate having them more then fixing them, i'll work on the same problem sometimes for weeks trying to figure it out. but that's generally in linux where you can't google every system option lol in windows it's generally easier. Make sure ya report back here with results cause if all that stuff I mentioned above passes I'd say Motherboard, which would really suck and I hope yours is still under the RMA time with newegg.