groudon185p

sounds like not enough power or overheat, even though you are running 8 gpus in there they may get hot, but also the 9800 gx2's take 250w's of power EACH, you NEED a higher power supply about 1250w's to power it sufficiently because idly it takes only like well not much but when your running a power ***** like crysis it pushes more power to the gpus to get some decent numbers out of it so goto newegg or something and look for a 1250w power supply, that will power it and should get no crashes, also might wanna "overclock" your fans to get a little more heat outa that system, sounds hot.