Normally I would suspect an over heating problem,but it doesn't sound like it stays powered up long enough to get hot.With that in mind I would suspect a hardware conflict.What I do is install an old but known good video card and try powering up,if that doesn't help me,then I reduce the amount of ram,series of elimination...It might be that the processor fan isn't working and the system is automatically shutting down to protect the processor. It could also be a RAM problem...... If all else fails my only guess would be that it is a faulty motherboard.............. I just thought of something and that is that you could be a short from the motherboard mounts????sometimes the board will short against the standoffs or the board is touching a part of the case that it didn't on the other case, take the board out of the case, find a place to rest it on,something non conductive!!!!!,plug in the power supply, put in your video card, attach your key board and fire it up, if it does the same thing,your board is cooked, if not ,you now have to find where the board is shrtn out.
Edited by Tech08, 01 June 2008 - 02:26 PM.