PSU problem?

Check to see how your temperatures are for your GPU or CPU. If you don't know how...try downloading Core Temp for checking your CPU and Evga Precision (have to register to download that though) for your GPU.

To thoroughly check with memtest86...use one ram at a time in each slot...may be time consuming but it's really the only way to check that it's absolutely not the memory. If you have anything overclocked...try putting it in default stock settings and try again to see if the freezing still occurs.

Im not an expert on these kind of problems but assuming you've gone through all the basic steps (check connections/seating of gpu, check temps, get latest drivers, tried a different psu, etc) and you suspect the power supply:

1)check out your voltages in everest or bios, like the +3.3v, +5v, +12v, etc. If the readings are too much different than what your psu specs out that might be the problem.
2)Another check would be to use an online "psu calculator" like Extreme, AAnet, OuterVision, or NewEgg's to see if your setup demands more than what your Coolmax is capable of.

If you could post info like when it happens (ie the second 3d starts or randmonly after the game starts), if this is a brand new build or if you've had the system for awhile and haven't had this problem before, or if you see any artifacting or hear a quiet but high-pitched squeeling noise, that would help others troubleshoot.

Good luck!

It's really hard to tell if the PSU is the culprit because you have to really rule out everything else before you get down to it. What would be helpful is if you have any spare parts (GPU/Memory/PSU) to use to rule it out. If you don't have any...try to borrow one from a friend or someone you know (if borrowing a PSU obviously make sure it's enough amps/wattage to power your system) and then you can work from there.

Your temperatures look good and since you don't have anything OC...you have less stuff to worry about. It now comes down to faulty hardware...find some spare parts and get testing. Once you find that nothing works...then you can get down to either the motherboard or PSU being the problem. The only time I ever had a PSU problem was because it wasn't strong enough. Symptoms were freezing, slight artifacts, and computer shutting off when playing a graphics intensive game. Computer shutting off made it pretty obvious. Since you just have freezing issues...it's harder to determine...so like I said if you have some spare parts...start testing.

One more thing I'd like to add...sometimes it's not always faulty hardware but how some hardware is set up. For example...I used to have freezing problems occur...not because I had faulty hardware...but from having too many optical drives (dvd-burner/dvd drive/blu-ray drive). Only hint I got was that my blu-ray drive would randomly disappear from *My Computer*. I disconnected the blu-ray drive and now everything seemed to be back to normal. I ended up just getting rid of all three optical drives and just buying a single blu-ray burner.

I just noticed something... your sig says you have a Coolmax V600, and the psu calculator recomended 700w? I googled your psu and its a 600w model.
Also, at idle, your +3.3v, +5v and +12v should read 3.3v, 4.97v, and 11.84v, respectivly. HWMonitor's readings are far too low, possibly meaning your system is trying to use more wattage than what your psu is capable of (not 100% sure though).

In case you have the wrong psu in sig and im wrong about HWMonitor's readings, then your next best bet will be to borrow a buddy's, or if you have a local computer store that will give full refund on an opened item, buy one to test and return it when done.

But my bet is your current one just isn't up to the task. Good luck and update us with what you find out!

MrLinky, I have feeling his PSU is the culprit as well. His total 12volt amperage is 37.5 (450/12) which is decently enough but the wattage is a bit low for a quad-core, two hard drives and a GTS 250. The PSU calculator more than likely is overrating everything because 700w is way too much but gosk is probably in the range of 450-500w during full load.

The best way to measure the rails would be with a multimeter. That will give you accurate readings versus software. Here's a helpful guide that I always suggest for this procedure. If the 12volt rail is fluctuating during load then that may explain for the crashes.

Gosk, just out of curiosity but can you re-run memtest and run tests 5 and 8? Try running both tests for about 3-5 loops. These tests seem to be a bit more strenuous on the memory than the defaults. Also if you can please run some stress tests on your processor to see what happens. Applications such as Prime 95 or OCCT are great for this. Another great way to load your GPU at 100% is to download ATITool and run the "3DView" function. It's a great tool for checking gpu temperatures and it's especially good if you're wanting to check the rails during load.

Good luck

Doubtful it is PSU.... 600W.. Is your GPU overclocked????

Jimibgood, see my post above. More than likely Coolmax is overrating this power supply which probably doesn't bring it close to the advertised wattage