OK mac pro with 2 quad core intel xeon.
the computer wont start from cold start most times.
the only time i can get it to start is to unplug and replug.
the ram lights come on for a few seconds and then all power off
i can keep trying and it will allways go off untill i unplug.
some think powersupply and some say logic board.
I'd like to test before automaticly assuming the PS is bad as they want a lot for a new one and if thats not the problem then iv'e done a lot of work for nothing.

anyway

I know how to test an ATX power supply but this computer is diferent.
Anyone know how i can test this 1.2kw power supply without removing 90% of the parts??

obviously the only way is surgical dissassemby or possably unplug directly at the power
supply? if this is the case then i would need to know whats what here. anyone know?

thanks

Just a Google search brings up this:

Power Mac G5: Power Supply Failures

More general:

mac pro power supply test - Google Search

Other issues with this same symptoms have a faulty power switch. Can you turn off from the power switch?

Hi john,

I have the same problem with my Power Mac.
Did you resolve it? How?

Thanks from Spain

Adrian

Originally Posted by johnjohnjohn

OK mac pro with 2 quad core intel xeon.
the computer wont start from cold start most times.
the only time i can get it to start is to unplug and replug.
the ram lights come on for a few seconds and then all power off
i can keep trying and it will allways go off untill i unplug.
some think powersupply and some say logic board.
I'd like to test before automaticly assuming the PS is bad as they want a lot for a new one and if thats not the problem then iv'e done a lot of work for nothing.

anyway

I know how to test an ATX power supply but this computer is diferent.
Anyone know how i can test this 1.2kw power supply without removing 90% of the parts??

obviously the only way is surgical dissassemby or possably unplug directly at the power
supply? if this is the case then i would need to know whats what here. anyone know?

thanks