I have had a x51 R3 with the GTX 960 for about 3 weeks and it is intermittently overheating while playing a game. I currently only have Doom 4 installed and sometimes I can play for an hour or more with no issues while other times in 10 minutes the game starts to slow down and when I go back to the desktop the GPU temp is in the 90's and the GPU fan is running 100%. I can then turn it off for about 10 minutes and start the game again and have no issues. I have opened the case a couple of times and don't see anything blocking the fans. I have talked to Dell and they had me run a stress test which was successful even though the GPU temps got in to the 90's and then he had me upgrade the BIOS and the PC was fine for a week and then it overheated last night while playing Doom 4 in 10 minutes. I shut it down and opened the case again and checked the fans for any blockage and started it up again. This time I played for over an hour with no issues. Dell has no answers is this happening to anyone else?