HD6850 freezing and pc restarts


Jul 8, 2009
Well a few weeks ago i went out and bought the xfx hd6850 card. I upgraded from a 4850.

PC specs

amd phenom 2 x2 550 at 3.82ghz
4gb ddr2 1066mhz corsair ram
550watt corsair psu
gigabyte ma790x-ud4p mobo
windows 7 64bit

This does not happen in all games, when i play dirt 3 its all fine but when i play starcraft 2 every now and then itl freeze and restart automatically. Now I have no idea why it does that sometimes i play for like 2 -3 hours and its fine and sometimes like half hour and it restarts. I know my temps are good because i have about 6 120mm fans and i turn them up while playing so thats not an issue. I read that Alot of people experience the same problem with the 6850 and 6870 cards. People suggested that it could be a driver issue well i did update them and have the latest ones. Some people said it could be the ram, but i figure if my computer just surfing the web, photoshop cs4, sony vegas pro 10 and all those work fine i dont think it is memory problems. Plus dirt 3, and tf2 all work fine it never restarted in those games. Also if it was a ram problem wouldnt it show up on boot up or possibly not even boot up ? I would run memtest but i cant pull out my sticks because i have a huge ass heatsink that blocks them in. The only way to take the heatsink of is to take the mobo out because there's a backplate to the heat sink. And of course my case does not have it cut out on the side so i could unscrew it easily. Bummmer. I could how ever test them together but your suppose to test the sticks 1 at a time.

Soo guys if you have any ideas or advice i would like that because im sick of my computer restarting as soon as i engage into action. Just ruins the game for me. I hope you guys can help me out. Thanks.
"Also if it was a ram problem wouldnt it show up on boot up or possibly not even boot up ?" < no. and yes you can run memtest86+ without removing ram sticks. Also run your hard drive manufacturers diagnostic. Re-install the game, since it only happens with starcraft. Also, you have an OC'd CPU. remove the OC and see what happens.