Im running windows 7 64 bit with 2 gtx 260 cards in and 4 gig of memory (ddr2 corsair dominator) and a corsair tx 750w psu.Since ive put my 2nd card in place i get part way through modern warfare 2 and the screen goes blank and on the odd occasion it blue screens with an error about recovering graphics drivers or something as it goes off quickly .can anyone help with this problem please ?? .