I cant overclock Q6600 without games crashing

Yes

No

What are the rest of your system specs? How far is the Q6600 overclocked? Sotck Cooler? Temps?

Usualy about 3 Ghz, however i have put it back to 2.4 and it is better but after a while it still occurs. I had stock cooler but got a new one which is pretty crap to ber honest. Temps are idle at about 45-52. Load i actualy hit 80C but usuasly 75 max

My friend had the same issue. It turned out I had to remove 2 sticks of RAM and return the CPU back to stock speeds due to bad memory. Try running Memtest on your memory to make sure that isn't an issue that is causing the problem.

Your CPU temps during gaming at 75 to 80 C will certainly cause your system the occasional freezing and hangs. Can you further describe your CPU cooler other than its pretty crap?

Sorry it took so long to get back to you (3 months later), the stock cooler is crap. I ended up getting the Cooler Master V8 which works wonders on the Q6600, which i own, you can save some money and purchase the Cooler Master 212P which i read reviews about it doing an excellent job, better in fact than the V8 but the V8 is nice to look at. For your cpu to run in the mid 70's is crazy, i ran prime95 with stock cooler @ 3GHz and it skyrocked to 65 in just 45seconds so i killed prime95. With the V8 i can run p95 with its peak at 55c at 3.3GHz, again from tests ive seen the Cooler Master 212P cools better and is half the cost of the V8, but if you like eye-candy get the V8 other wise get the 212P.