Re: Spontaneous Black Screen
Check your computer's temperatures to make sure no components are overheating, especially the GPU.
Check your PSU's voltages in BIOS too. Make sure that all the voltages are within .12-.16 of what they are supposed to be.
If everything checks out at this point, Put in a spare GPU if you have one and see if the problem resolves. If no, then we'll go from there.
RD-PC -//- i7 950 // Evga x58 SLI // 3x2 OCZ PC3-12800 // 2x Evga GTX470 // Corsair HX850 // SilverStone TJ07