MP 1,1-5,1 Help! - Mac Pro 3,1 (2008), Won’t boot

[PerkeoRoger]

Hi

Can anybody help me troubleshooting my 3,1 Mac Pro (2008)?

I recently got my hands on a Mac Pro 3,1 that is not booting. When I press the power button the white led stays steady, no chime and the fans start.

I don’t know almost anything about this computer, other than the fact that this unit may have been diagnosed with a bad power supply, but it’s not guaranteed.

I haven’t been able to discover which CPU’s it has but it had two graphics cards inside, one nvidea GeForce 750 (2gb), and one nvidea 8800gt. I think it may also be important to mention it didn’t came with any disk, (hdd or ssd), and that all of the ram slots are full.

I have been reading the manual and trying to diagnose it using the led’s on the board,

- when the button is NOT pressed:
SLP - off
STBY - off
ERRB - red
ERRA - off
OT B - off
OT A - off
GPU - off
PWRG - off
EFI - off

- when the button is pressed:
SLP - off
STBY - yellow
ERRB - red
ERRA - off
OT B - off
OT A - off
GPU - green
PWRG - green
EFI - off

- I have also pressed the reset switch but nothing happens.

The computer does not show any video in any of the graphics cards.
I have verified the voltage of the motherboard and everything seems good (3.00 V)

I have tried to see if it would show anything when a disk with El Capitan taken from a working MacBook 2009.

I you happen to know something about this please give me a hint!

Thank you very much for your time!

 

[tsialex]

Mac Pro even beeps?

Did you confirmed that the GPUs are working?

Did you tried to clean the memory risers? Tested one riser at a time? Any memory riser LEDs lit?

 

[PerkeoRoger]

Mac Pro even beeps?

Did you confirmed that the GPUs are working?

Did you tried to clean the memory risers? Tested one riser at a time? Any memory riser LEDs lithos

Hi,

No the Mac Pro does not make any sound or chime.
The only thing the gpus do right now is spinning the fans.

I have 8 sticks of ram with dissipador, I have gone through the service manual and tried all of the combinations presented there.

I have tried cleaning the risers, but nothing.

The only light on inside of the computer is the ERRB on red and I have noticed a new flashing light on OT A. The risers only flash four red light when I turn the computer on.

I think that the attached scenario present on the service manual is the one I am facing..

 

[tsialex]

Did you verified the RTC battery voltage? A non-working RTC makes the Mac Pro fail at POST. Do you have any AppleOEM GPUs? You only have pre-boot configuration support with an AppleOEM (8800GT?) unless the GT750 is flashed.

You can boot an early-2008 with just one Xeon present, installed to processor socket B, the lower one. Test both processors one at a time with socket B:

MacPro 3.1 early 2008 Quad core 2.8. upgr… - Apple Community

discussions.apple.com

With the ERRB LED lit, seems to me a dead logic board, but before starting looking one to buy I would do the elimination game.

If you have access to another working early-2008 Mac Pro test the PSU with the working early-2008, just to eliminate it, since PSUs are tricky to test without load and correct signals.

 

[PerkeoRoger]

Yes I did verified the voltage on the battery and it was 3V.

I don’t have access to another Mac Pro to try that, but I can try swapping the processors and see if the light follows.

Would you say that is a good idea?

By the way are you suggesting me to try the GPUs for example on a windows machine?

 

[tsialex]

Yes I did verified the voltage on the battery and it was 3V.

I don’t have access to another Mac Pro to try that, but I can try swapping the processors and see if the light follows.

Would you say that is a good idea?

Yes.

By the way are you suggesting me to try the GPUs for example on a windows machine?

For the 8800GT you'll probably need an old BIOS PC, this GPU will not work with a modern UEFI class 4 PC (usually anything past Intel 8th gen does not have CSM/legacy support anymore), but the GT750 will probably work.

The 8800GT is AppleOEM?

 

[PerkeoRoger]

Yes.



For the 8800GT you'll probably need an old BIOS PC, this GPU will not work with a modern UEFI class 4 PC (usually anything past Intel 8th gen does not have CSM/legacy support anymore), but the GT750 will probably work.

The 8800GT is AppleOEM?

Hi,

I have exchanged the processors and after multiple experiments I ave been able to confirm the following:

- the ERRB light goes away when any of the processors is installed on socket A, with the other socket empty

-when both processors are installed in socket a and b, the result will always be the same, the ERRB light turns on

- when any of the processors is installed in socket b, both with the other empty or full, the light will turn on


There’s still no chime.

Any thought on this?

 

[tsialex]

Socket B is the main one with an early-2008, if you are getting ERRB LED lit whenever you install a processor to it, unfortunately the most probable is that you have a defective logic board.

 

[PerkeoRoger]

Socket B is the main one with an early-2008, if you are getting ERRB LED lit whenever you install a processor to it, unfortunately the most probable is that you have a defective logic board.

Does that mean that I would need to buy a logic board to get the Mac to boot?

I saw there were some Mac Pros 2008 with only one cpu,

Can’t I just use it for sometime without any cpu on the socket b?

 

[tsialex]

Does that mean that I would need to buy a logic board to get the Mac to boot?

Yes.

I saw there were some Mac Pros 2008 with only one cpu,

Yes, socket-B installed CPU. I've sent you the link to the pictures of one.

Can’t I just use it for sometime without any cpu on the socket b?

Nope, you need to have a CPU installed to socket B for the Mac Pro to work.

 

[PerkeoRoger]

Yes.



Yes, socket-B installed CPU. I've sent you the link to the pictures of one.



Nope, you need to have a CPU installed to socket B for the Mac Pro to work.

Would you say it is worth the price (100€) that I would need to pay, or should I just sell it for parts?

 

[tsialex]

Would you say it is worth the price (100€) that I would need to pay, or should I just sell it for parts?

You have to make some calculations if is worth or not for you.

I'd look at an early-2009/mid-2010/mid-2012, if you have some patience and search everyday for a while you can get a barbebones working one for not much more money.

Classic Mac Pros by now demand some maintenance and a lot of people does not have the skills/time to do it and just sell it cheaply.

 

[PerkeoRoger]

You have to make some calculations if is worth or not for you.

I'd look at an early-2009/mid-2010/mid-2012, if you have some patience and search everyday for a while you can get a barbebones working one for not much more money.

Classic Mac Pros by now demand some maintenance and a lot of people does not have the skills/time to do it and just sell it cheaply.

I understand and the only thing I can say is that I am passionate about the design of these Macs and the idea of an upgradable Mac tower.

I have been thinking and I figured I can’t be shure if the problem is indeed the logic board and wasting around 100€ on it doesn’t seem that safe.

My problem now is to decide if I let my desire of having one of these machine preferably a 5,1 working to control or if I invest in parts.

After searching around the prices on ebay for the 5,1 are always (Mac+shipping+vat) around 400€ to 500€ and that is certainly more than the amount I would be ready to pay for it.

This would never need to be my main machine as I have my trusty MacBook with Apple silicon. I will try to do what you say and continue searching!

 

[PerkeoRoger]

error

 

[tsialex]

I'd look on the local version of FB MarketPlace/Craigslist/etc instead of eBay. There are several reports here of people in the EU finding working examples on the cheap at e-recyclers.

Another thing that I'd look besides a MacPro4,1/5,1 is an early-2008 with a banged up case, two makes one and you can sell any unneeded working parts.

 

[PerkeoRoger]

I'd look on the local version of FB MarketPlace/Craigslist/etc instead of eBay. There are several reports here of people in the EU finding working examples on the cheap at e-recyclers.

Another thing that I'd look besides a MacPro4,1/5,1 is an early-2008 with a banged up case, two makes one and you can sell any unneeded working parts.

That’s good advice thank you.

I will mention that prior to this Mac Pro 3,1 I had been searching on e recyclers for months.

I will continue my search!