I have an 8800gts 512 and had it overclocked and it was completely stable. When I realized oc'ing it barely makes a difference I went back to stock clocks. The computer has been stable for the month and a half ive had it or so but now sometimes the monitor wont wake back up when it goes to sleep and I have to do a few hard reboots. Is this a GPU problem? Should I send it back?