Hey guys, 
 
I was just finishing a recording session with a client, when I bumped my computer case and it shut right off. I didn't really think anything of it at the time, but I went back down and pushed the power button -- nothing. I just built this computer a few months ago. So I took it upstairs to take a look at it, everything seemed in order, so I plugged it in on it's side and it powered up. I flipped it upright and it booted fine. So I put it back in the studio and hit the power button, the CPU fan spins once then stops, like it was doing before. I took it out of the desk put it on it's side and again it booted up. I lifted it back into place while it was running, and it's running right now. Any ideas? I have no idea what would cause this behaviour. Bizarre. 

First guess is overheating. Your sure all the fans are working correctly?
John
 
 

Yes, it's been running for or a few hours now, no problem, all fans are working fine. Unless I did something wrong when I put the artic silver on, but I followed the directions closely.

Check that everything is seated properly - RAM, graphics card etc
I would remove them all and reseat them
 
Also make sure you haven't go a buildup of dust clogging the fans
 
Is there decent airflow in your studio?

I'll reseat everything later today and let you know. there is no dust in it, the case is filtered (filter is clean) and it's just been built. I really doubt it's overheating, I've never had an issue with any other computer in the same spot, so airflow shouldn't be a problem. 
 
I was almost leaning to the motherboard was shorting out. It's funny that it runs no problem on it's side, but then as soon as you stand it up that's when there's a problem. I also have an aftermarket Cooler Master heatsink on the processor, so I'm wondering if maybe I didn't seat it properly. But, it seems to be on there very well. 

stokedboss
Hey guys, 
 
I was just finishing a recording session with a client, when I bumped my computer case and it shut right off. I didn't really think anything of it at the time, but I went back down and pushed the power button -- nothing. I just built this computer a few months ago. So I took it upstairs to take a look at it, everything seemed in order, so I plugged it in on it's side and it powered up. I flipped it upright and it booted fine. So I put it back in the studio and hit the power button, the CPU fan spins once then stops, like it was doing before. I took it out of the desk put it on it's side and again it booted up. I lifted it back into place while it was running, and it's running right now. Any ideas? I have no idea what would cause this behaviour. Bizarre. 

Re-seat both power connections to the motherboard... along with RAM and video card.
If that doesn't stock the behavior, you may have a short in the PS itself.
If that's the case, swap out the PS and you should be good.

I was thinking it might be the PS, I really hope it isn't -- it's brand new, and I don't have a spare to test it with :(

If it's brand new it will still be under warranty.

Loose screw shorting out the motherboard?  As much of the PIA it is, I would pull the motherboard and see if something is trapped underneath.  It would also give you a chance to make sure the MB mounts are securely installed.
 
Did you check the logs to see if there were any messages about overheating? (Control Panel, Event Logs)
 
-JJ

"I also have an aftermarket Cooler Master heatsink on the processor" Although it may be okay, it may not be if a cheap one. It is like automobile parts. Buy the manufacturer's parts (3 times as much at least) and it works fine. By aftermarket parts (3 times cheaper and last 3 times shorter) and replace every year or two.