Chosen Solution
I was given a Mac Pro 8x with an apparently bad power supply. I have replaced the power supply with a working one purchased on Ebay. Now, when I power it on, the LED over the power button comes on and stays on. All of the fans spin up, but do not seem to be max RPM. I see the memory boards light up then go off. I hear the HDs spin up. Here is what I don’t hear/see. There is no Mac Chime, video never comes on. When I depress the DIAG_LED button I see TRICKLE, GPU_PRESENT, PWR_ON but I never see EFI light up.
Here is what I have done to troubleshoot. I have tried 3 different video cards in all the available slots. The original GeForce 7300 GT, GeForce GTS 450 and an Asus EAH3450. I have replaced the onboard battery CR2032 I have removed all HDs, swapped through all the memory modules and in every combination from 1 GB to 4 GB. I still get nothing. I have read this solution: Powers On but No Video And still nothing. Any help that can be provided would be greatly appreciated. I went ahead and removed the CPUs and they are in a state I have never seen before. This is the First MacPro I have disassembled and I have never seen CPUs/Heatsinks with this sort of residue on them. I have tried to clean them off but with no real effect.
Is this normal? Peter Barton
I found a replacement CPU and that did the trick. I was able to get to the Apple Load screen!
