I've tried back and forth with OC lately.
I first found a GPU OC that i liked (tested fine with 3Dmark11) and played a bit with no problems.
Afterwords i found a CPU OC that i was satisfied with that tested fine with Prime95.
Then i did a Furmark test and the GPU passed it (got 3000something score, not sure if that's good) and didn't go past 72c.
Finally i wanted to try 3Dmark11 again when they both had an OC.
This i can't pass, i get to the 3rd test and it crashes with an "out of memory" error.
Does this mean i should dial things down? As far as i know 3Dmark is a more reliable test.
Using a Mist 1000w Psu (think it's only sold in Norway but, it should be more than good enough)
Edit: Guess it's a good idea to post my speccs.
i5-3570k @ 4.2ghz
MSI GTX660Ti Power Edition (OC removed at the moment)
Asus P8Z77-V Pro Mobo
8gb Corsair Vengance 1600mhz
Kingston HyperX 120gb SSD
Mist 1000w PSU
Good tower with good cooling, etc.