MacPro 4.1 won't boot up, no power

[tfronau]

Early 2009 MacPro 4.1Quad 2.93 GHz, 8 GB, 10.6.8
When I turn it off, it won't boot. No light no power nothing. I have to unplug the computer, remove the cover, reset the switches on the motherboard, plug it back in, and then it will startup. Why? What would cause thiis?

 

[highdefw]

dead power supply? The easiest way to know what's wrong is to take it to Apple.

 

[Dr. Stealth]

Check the Battery

Check the battery. Or just replace it to be sure. It's cheap. It's under your graphics card.

Could be power supply failing though.

 

[tfronau]

Won't boot, no power unless I reset

I replaced the battery, no change.

The power supply seems to work once I push the reset buttons on the motherboard. I don't think it is the ps. Can anyone tell me what the reset buttons on the MB do?

 

[tfronau]

It was the power switch, but they had to replace the entire case.