I just built my pc i plugged in the cables and now when i press the power button the fans turn on but then after 1/2 a second it turns off

Primary reasons for instant shutdown: >Bad heatsink and/or thermal paste install. Pull your h/sink, make sure the grease is applied properly. AND make sure your heatsink is mounted square and even on the CPU. >Reset your BIOS back to default settings. Give a man a fish and you feed him for a day; Teach a man to fish and you feed him for a lifetime; Then industry pollutes the water and kills all the fish.

I have just built my own PC with a considerably more modest spec than yours. I did also have a similar problem about which I was tearing my hair out! luckily after hecking the inside of my case I found that I had neglected to plug in the 12volt line form the PSU into the mainboard. basic but (in my case) very esaily overlooked. If you have any diagnositic LEDs fitted it is also worth checking these with your manual to see if these offer any help. Another potential problem can be overhaeting, check to see that your CPU cooler is proberly itted (it should be frustrtingly difficult to remove) and that you have some sort of thermal paste or tape joining your CPU and your Heatsink. If you bought your componensts second-hand or from Ebay then you unfortunatly also have to condsider that you have bee sold naff kit :-( Also ALWAYS use anti-static precuatons before poking around inside your case. Apart from that all I can give you is my sympathy, goodluvk, I hope its just a minor problem that you have overlooked and nothing more serious. Merry Christmass Never argue with the fellow that packs your parachute

i had this problem on one i built, but it would last 2-3 seconds before going off, and then it would not let me try again unless i actually unplugged power cable from wall socket for a few seconds. The problem was because the jumper was missing from the Clear CMOS pins. It was not in wrong position on the pins, it was actually missing. Luckily did not take me long to find it - only beacuse I was building two systems with same mobos and put them next to eachother to compare them.