computer will not turn on while upright

[LikwidNitrogen]

I'm building a computer for someone, and the darn thing won't power on while in upright position (it's a midtower). Works fine laying on its side. I've double checked motherboard power connector, power button connector, disconnected all other devices etc. Is this a bad power supply? Maybe a slighty loose motherboard?

 

[Chaotic42]

Sounds like you've got a stump (the thing you screw the board into) touching the bottom of the motherboard. Take it out and make sure all of them line up with holes.

 

[JZilla]

Try to loosen the screws holding the mobo.

 

[bcterps]

You might have a loose screw stuck somewhere causing a short. Try unscrewing the mobo from the case to see if there is a screw stuck under the mobo.

 

[Goi]

It *should* be a connection problem, although its remotely possible that you have insufficient power.