Hi, I have recently gotten Guild Wars + Factions to play with a friend of mine. His computer runs it without any problems, crashes, or reboots.. on high settings.. Now the funny thing is, my computer is faster than his, can run Crysis on high settings, Bioshock on high, and supreme commander without any problems. But after playing this game for around 10-15 minutes I crash due to the Gw.exe Assertion error.. Ive read the old threads about it, have tried -image, -dsound, -noshaders and nothing works.. ive uninstalled reinstalled and everything.. still crashes.. Any help would be deeply appreciated!

My Specs:
AMD 64 X2 4800+ Dual 2.4Ghz
2 gigs ram
BFG NVidia 8800GT 512MB OC
550w PSU
Creative X-Fi Xtreme Gamer sound card
5.1 Surround Sound speakers

All drivers updated as of like 1 week ago so that shouldnt be a problem.