BDOD Only When Playing Blizzard Games?

First off my Specs:

-Windows 7 x64
-Asus P5k
-Intel E8500, not OC'ed
-4850 crossfire
-3 x 2GB DDR2 800 (2 chips are transend and, other is dynet running in dual channel asymmetric mode)
-550 watt Coolermaster PSU
-Coolermaster storm scout case, so loads of Fans.
-250GB seagate primary and 2 terrabyte seagate secondary.

First off, let me explain the whole situation. A few months ago my Graphics card blew and I sent it in for replacement (was a Asus 4850 512mb). The card was in crossfire with my other 4850, the force3d version and while the asus one was in I was using it as the primary card. So a few days ago (yes i know - sent it in a few MONTHS ago and only got it back now. I was procrastinating, we all do it) I got the card back and I put it back in my machine and installed the latest 11.12 drivers.

This is where the problem started. All of a sudden while playing Sc2 I got graphical corruption followed by a BSOD. My immediate thought was it must be the new drivers and so I went back to 11.11 drivers. But as you can assume the problem still persisted. Next I ran all kinds of stress tests:

- Prime95 for an hour

- Memtest for 3 hours

- multiple runs of 3DMark Vantage which all ended fine and without a BSOD But yet as soon as I launch WC3 frozen throne to play a game of DOTA, sh** starts happening. 15min into a game I get the same graphical corruption I get in SC2, but in WC3 it sometimes goes away almost as if the driver restarts, but eventually ends up in a BSOD.

Next thing I did was put the force 3d card as my primary and ran it without the asus card because I assumed it was the card that was causing problem yet again. But still the same graphical corruption and BSOD. The strange thing is that this only happens in blizzard games and not when I'm playing CoD mw3 or any other games for that matter. I've played for hours on end in mw3 and no problems. I even got the files for WoW from a friend and tested to see if I was right and I was as a BSOD soon occurred. After scourging the internet I found that a lot of people have had relativity the same errors with overheating components, but I'm pretty sure my temps are normal but, just in case, I will post them anyways

MB - 38 Idle, 40 - 43 Load
Processor - 39 Idle, 50 - 55 Load
Graphics (Asus card) - 38 Idle, 51 Load
Graphics (Force3D card) 41 Idle, 52 - 55 Load

To shorten the story a hell of a lot I ended up formating (after running driver sweeper multiple times in safe mode and re-installing the AMD drivers multiple times), but still the same?I am convinced it is a driver problem, as ATI drivers are notorious for causing trouble and the fact that on WC3 sometimes the BSOD's are somehow avoided by what I think is Windows pulling the driver back from the depths of hell Another reason is if I ctrl + alt + del when the corruption starts happening and return to desktop windows pops up and says "Display driver has stopped responding and has recovered".