I recently bought a new case (Antec Sonata II). After moving my previosly functioning PC into it, the motherboard (Asus P5B-Deluxe) started powering off randomly, usually within a minute or two of powering up. I tried replacing the power supply with a known good one (the PS from my previous chassis), and still it exhibits the same behavior. I tried resetting CMOS on the board, I tried reseating the PCI cards, and I tried booting without peripherals. No luck The only difference between this setup in the new chassis and my original working one is that I'm using a new SATA disk. What could possibly be causing this? Any ideas/suggestions?
It could be a number of things, first off i would try powering up without the new Hard Drive, if that fails it looks like you have a faulty motherboard.
Take the motherboard out of the case and place it on a non-conductive, flat surface with minimal components: CPU, CPU heatsink, 1 stick of RAM installed, power supply, video card. Try powering it up and letting it run like that. Add another component until you get a failure. Make sure that all power connections on the motherboard are plugged in.
Yes, that SATA drive might be bad. Does it run without it? When a MoNo powers off after a few mins it can me the CPU is overheating. You may have unset the heatsink just a bit. That has happended to me.
If its not a mobo problem.. then chk out ur cabinets power switch cable... if the cable is damaged or something like tat, chances for mobo to get switched off is there... remove ur mobo out of tat case and try running it..dont use the power switch of ur case... jus short two pins on ur board.. refer manual to find those two pins...
Thanks everyone for the replies. In the process of following your advice, I realized that the CPU fan was damaged, and wasn't mounting on the board properly. As a result, the CPU was running too hot, and that's why the motherboard was shutting off. I replaced it, and now everything is fine.