MacPro 5,1 is not booting anymore

Coyote2006

macrumors 6502a
Original poster
Apr 16, 2006
501
229
Hi, Mac MacPro 5,1 is not booting anymore. It starts and the GPU-Fan seems to run endlessly but the screen stays black. The Mac is not booting. I've already switched RAM but without success. Any ideas what could be wrong?
 

tsialex

macrumors 604
Jun 13, 2016
7,389
8,102
Brazil
Hi, Mac MacPro 5,1 is not booting anymore. It starts and the GPU-Fan seems to run endlessly but the screen stays black. The Mac is not booting. I've already switched RAM but without success. Any ideas what could be wrong?
Do you have a Mac EFI GPU to check if it's a hardware or a software problem?
 

tsialex

macrumors 604
Jun 13, 2016
7,389
8,102
Brazil
I've got the same problem with the Radeon 4870 and a flashed 680.
If you don't get the chime and nothing shows on the screen, the next step is to check diagnostics less of the logic board. If EFI led is off, you have a brick.
 

tsialex

macrumors 604
Jun 13, 2016
7,389
8,102
Brazil
no chime, just the fan of the GPU running
Like I wrote, you need to check the diagnostics leds on the backplane. If EFI is off, you have three options:

you have 3 options:
  1. Replace the backplane.
  2. Buy a Mac Pro MATT card.
  3. Desolder, externally reprogram the SPI flash memory, solder again, you can read all the process starting here #929.
 

Coyote2006

macrumors 6502a
Original poster
Apr 16, 2006
501
229
Thanks a lot tsialex. How do I check the diagnostics leds on the backplane? Sorry, I've never done this.
 

Coyote2006

macrumors 6502a
Original poster
Apr 16, 2006
501
229
unfortunately, no
[doublepost=1544045756][/doublepost]You think that this might be related to the PSU?
 
Last edited:

Coyote2006

macrumors 6502a
Original poster
Apr 16, 2006
501
229
Thanks ldfa, you seem to be right. Looks like this leads to problems on the processor board.
 
Last edited:

Coyote2006

macrumors 6502a
Original poster
Apr 16, 2006
501
229
4,1>5,1 (single CPU) and I updated the CPU about 3 years ago. One of the Northbridge rivets was/is not completely upright. Maybe that could cause the problem. I'll try to organise new rivets, clean the CPU and the Northbridge chip and reinstall it. Do you have a sourse for the rivets? I just found some in China and the delivery takes about 2-3 weeks.
 

tsialex

macrumors 604
Jun 13, 2016
7,389
8,102
Brazil
4,1>5,1 (single CPU) and I updated the CPU about 3 years ago. One of the Northbridge rivets was/is not completely upright. Maybe that could cause the problem. I'll try to organise new rivets, clean the CPU and the Northbridge chip and reinstall it. Do you have a sourse for the rivets? I just found some in China and the delivery takes about 2-3 weeks.
I know that you can buy the Mac mini CPU heatsink original ones from Digikey, if I remember correctly, but I bought a package of 100 of the generic one from China last year, 60 days to arrive here. The Mac mini ones fit better than the generic ones. I never saw the real Mac Pro ones for sale.
 

Coyote2006

macrumors 6502a
Original poster
Apr 16, 2006
501
229
I know that you can buy the Mac mini CPU heatsink original ones from Digikey, if I remember correctly, but I bought a package of 100 of the generic one from China last year, 60 days to arrive here. The Mac mini ones fit better than the generic ones. I never saw the real Mac Pro ones for sale.
Thanks for the info :)
 

Coyote2006

macrumors 6502a
Original poster
Apr 16, 2006
501
229
Sorry, I got it from a post on netkas, years ago. Tried to found it now, but didn't succeed.
ok, no problem. thanks for your great support!

I've also found and ordered a processor board on ebay. At least I have a backup board then :)
 
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