System shuts down after a few minutes

[indigox3]

About a week ago, one of my hard drives began acting up, so I removed it, and got a new one, did a fresh OS install, and once I verified everything was working, I plugged in my damaged drive to copy some data off of it. Everything worked fine, I got most of my data off the drive, and shut down the computer for the night.

 

The next day, my system wouldn't start up at all. After pressing the power button nothing happened. No post, no fans spinning up, nothing.

 

I suspected that something happened to the PSU (Antec smart power 450w) so I removed it from the system and shorted the green and black pins. The fans did not spin up, and no voltage on the motherboard connector pins.

 

So I got a new PSU (Corsair TX 750), and now the system starts up, but then shuts down after a minute or two. I checked the cpu/motherboard temp in the bios and they were around 47 degrees. I also touched the side of the cpu heat sink and its warm, but not hot. No burning smells or smoke.

 

I've tried the following: (pretty much in this order)

- reseat all the power plugs

- reseat the ram (4 sticks total)

- unplugged the case fan

- removed 2 sticks of ram

- removed the other 2 sticks of ram, and put the other 2 back in

- unplugged all the hard drives

- unplugged the cd drive

- swapped out the video card

- removed the video card completely

- removed the motherboard battery

- changed the wall outlet the system was plugged into

- removed all usb and front panel (except the power switch) headers from the motherboard

 

Right now, I only have the motherboard, cpu, and ram connected to the psu. Everything else has been removed from the system and it still shuts down after a minute or so.

 

I'm pretty much hopelessly stuck at this point :(:

[Synthohol]

will it stay in the bios for a couple hours without shutting down?

[indigox3]

No, even when i'm in the bios it shuts down after a minute or so. (also I checked the voltages and temps from the bios and they seem ok. Nothing fluctuates rght before the shutdown)

[RAM GUY]

I would recommend you try this test, and if the PSU gives you the same behavior then use the "Request an RMA" link on the left side of this page. If the PSU turns on and stays on, then the PSU is getting a signal from some other component to shut off, and replacing the PSU may not resolve the problem. You may want to test it in a different system to be sure.