I built my own computer last summer, it consists of: MOBO: Asus P5E3 DELUXE/WIFI-AP MEMORY: Corsair TW3X4G1333C9DHX 2x2048MB (tot. 4096MB) DDR3 1333MHz CPU: Intel Core 2 QUAD Q9450 2.66GHz 12MB FSB1333 GRAPHIC: Asus Extreme GeForce 8800GTX 768MB DDR3 My problem is that it craches all the time. when i have both of the memory cards in it hangs more frequently, but when i have only one it took a bit longer. This was under Vista, and ive been only using one of the memory cards for a hole year. Last month i installed Windows 7, and it can crash after 5 minutes now. Ive had the mobo tested at the store i bought it and they found no problems, they even tested it with my memory cards. But im not sure that they tested it, since i did not buy them there. I believe that its the memory cards. Ive allso tested the computer with MemTest88 (something like that name), and it found fault. Any tips??? i cant use my compter now... its reaaally annoying. and i cant go out and by new memory to test with, i would be able to return them after the test.