Mac Pro 2008 3,1 Troubleshooting

[benjapo]

Hi All,

This is my first post in this forum.

I have a Mac Pro 2008 3,1.
Last week it stopped booting properly. Fans would spin up but no boot chime. Removing the Graphics Card, HDD's, and all RAM didn't change anything.
The diagnostic LED's revealed:
a steady yellow in STBY
a steady green in PWRG
a blinking yellow in EFI
(all other LED's were off)

I brought it to a local repair shop, they said it needed a new mobo. And instead of paying them to do it I got one on ebay and changed it out.

With this new mobo the symptom remains but now the LED's reveal:
a steady yellow in STBY
a steady green in EFI
(all other LED's are off)
Removing the Graphics Card, HDD's, and all RAM doesn't change anything.

Does this mean I now need a new Power Supply? Maybe I got a worse mobo? Thoughts?
Thanks!

-Ben

 

[666sheep]

Try this on your original board: http://support.apple.com/kb/DL94
It would need RAM installed at least.
What graphic card does it have?
Did you reset SMC properly?
Have you tried to check coin battery voltage? This is unlike cause of this booting behavior, but some people reported that replacing it has solved their issue.

 

[OS6-OSX]

http://thenextweb.com/lifehacks/2010/12/04/how-when-why-to-reset-the-pram-smc-on-your-mac/

 

[benjapo]

Thanks for the quick replies!

On both boards I've reset SMC via these 3 methods:
-leaving it unplugged overnight
-unplugging it and pressing the power for 5 secs
-pressing the SMC button on the motherboard (the one below the 4th HDD tray).

It doesn't get far enough into the boot process to reset PRAM. (it hangs before the boot chime)

As far as the graphics cards, I've switched between the stock ATI card that came with it, and the Nvidia Quadro 4000. Both of them (and using none of them) yield the same result.

I'll try the firmware restoration on the original board.

I don't know how to check coin-battery-voltage. But I imagine a replacement would be cheap?

 

[brand]

I brought it to a local repair shop, they said it needed a new mobo. And instead of paying them to do it I got one on ebay and changed it out.

With this new mobo the symptom remains but now the LED's reveal:
a steady yellow in STBY
a steady green in EFI
(all other LED's are off)
Removing the Graphics Card, HDD's, and all RAM doesn't change anything.

Does this mean I now need a new Power Supply? Maybe I got a worse mobo? Thoughts?

Take it to someone that knows what they are doing.

 

[benjapo]

Take it to someone that knows what they are doing.