Bad PSU or bad Mobo?

[XMonkey-v2.0]

I recently swapped out my old motherboard with a new one (same model, same everything else in the computer) and got it all put together and went to turn it on but it did something I haven't seen before. It will boot up for 1 second or less, everything turning on, and then shut down. If I press the power switch again nothing happens and I have to flip the power switch in the back off then on, but then it does the same thing.

Now, I have reason to believe the motherboard might be DOA (ebay seller I got it from was recently suspended for reasons they couldn't disclose...), but it almost seems like a PSU problem. Has anyone seen this sort of behavior out of a dead PSU?

Tomorrow I'll try using it with the bare essentials and maybe try jumpering it, if that all fails I might have to put in my old mobo and test it.

 

[XMonkey-v2.0]

Update.. unplugged everything except CPU fan + video card + mobo, did the same thing. Cleared the CMOS, same thing (except now I don't even need to use the power switch as it won't work). Finally I jumpered the power supply and it turned on fine and powered a few fans. I'll try plugging some more things into it, but I can't think its the PSU anymore....

Time to file a Paypal claim

 

[unhappy_mage]

Have you checked what voltages it's producing? Get a multimeter and check at least the +5 and +12 voltages.

 

[XMonkey-v2.0]

It's the mobo and I got scammed, the jackass even took off the part number and serial number sticker on the back of the bad mobo so I couldn't return it if I wanted to.