Hi, I recently Upgraded My Computer, rather, I Got a new computer and took 2 parks from my old one. lol I took the parts to a computer tech to have it built. I have Asus - P6X56D Premium Motherboard Intel I7950 3.07ghz Processor Corsair 850Watt PSU ATI Radeon HD 5770 1gig Video Card Intel x25-M 80gig SSD harddrive Western Digital 120G hardrive Corsair XMS 3 DDR3 6 Gigs (3x2gig sticks) ( CMX6GX3M3A1600C9 ) Windows 7 64bit Operating System Loaded on the SSD 2 120mm intake fans on front, 120mm intake fan on case side. 200mm exsaust fan on case top. 120mm exsaust fan on back. Obviosuly the CPU has a fan on it's heat sink as well. I just got the computer less than 3 weeks Ago, Originally with a different Video Card and PSU. I started getting Black Screens during the Very first Day of use. I've Upgraded the Graphics card to the most up to date Graphics. It started getting black Screen lock ups in Games Like Starcraft 2, Aion, Civilization 5, and Hon I started reading tech forums and asking my Computer Tech who built my machine. Initial thoughts were Power Supply, so I went from a 55W supply to my 850 Watt I have now. Then I thought it was a CPU overheating *(even though my Asus Software never said my cpu got above 74 celsius. so I bought the optional side case fan and put silver thermal compound on the cpu/heatsink. Still having problems, I tried my dads ATI Radeon HD4650 (I think). It seemed to solve the issue but I don't know if that is because the games couldn't use their full potential or not. But seeing how it seemed to make it better, I went to the store and Re bought my ATI Radeon HD 5770. The problem started occurring again with the new graphics card. I'm at a loss for what to do. Temperatures are always fine (40-64 celsius normally). The only thing I've heard that I haven't really attempted is that my motherboard may be picky about ram voltage and timings. It seems to run fine though. but I'm not sure really how to test the memory or cpu. Note- I have been able to run Civ 5 in Dirext X 9 mode as opposed to DX11 and I have been able to Run HoN continuously if I turn the graphics down to medium. Forgot to mention that I don't overclock anything manually, though I know my asus board software regulates my CPU to +3%. What can I do? it's not the PSU, shouldn't be the card (brand new). Doesn't seem to be Heat.