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jave808

macrumors member
Original poster
Apr 13, 2023
41
0
Newcastle NSW Australia
Hi
A while back I picked up an old Mac Pro 4,1 (early 2009) for nix. Only now have I had a chance to look at it.

It powers up, the power LED is white (if that means anything), front and rear fans spin, and I can hear the DVD drive clunking around, so something is happening.

But I have no display or even the "chime". There is a red LED on down near the RAM slots. I have some 16GB DDR3 ECC RDIMMS that I tried in one slot but the LED was still red on powering up. I'm not 100% what RAM these Macs take or what their max capacity is.

There is no hard drive or SSD installed. Would that stop it from booting up?

The video card installed was I believe a GT120 512MB card. I don't know if this card is faulty or not. I could try it in another basic Intel based PC and see if it shows anything. Or is it hardwired for Apples only? I have access to another nvidia card - GTX1050Ti - but I doubt that would work.

What else could I try before I scrap it?
 

bax2023

macrumors regular
Nov 14, 2023
124
158
Serbia
There is a red LED on down near the RAM slots.
Inspect exactly which LED is lit red and act accordingly. It can point out to exact memory slot with faulty RAM stick. Those lights could also point out that maybe someone tried to change CPU(s) and did not tighten CPU cooler properly and because of that CPU(s) do not have proper contact with pins bellow.

But this is the first step, inspect those RED lights. And no, missing of HDD/SSD can't be reason for this behavior.
 

tsialex

Contributor
Jun 13, 2016
13,454
13,601
Hi
A while back I picked up an old Mac Pro 4,1 (early 2009) for nix. Only now have I had a chance to look at it.

It powers up, the power LED is white (if that means anything), front and rear fans spin, and I can hear the DVD drive clunking around, so something is happening.

But I have no display or even the "chime".

EFI_DONE LED?

There is a red LED on down near the RAM slots. I have some 16GB DDR3 ECC RDIMMS that I tried in one slot but the LED was still red on powering up.

One red LED means one of the channels of the memory controller have a problem. Could be the Xeon, could be the CPU tray.

I'm not 100% what RAM these Macs take or what their max capacity is.

16GB without manual config, so, should work.

There is no hard drive or SSD installed. Would that stop it from booting up?

No, the display should work, with a grey screen and then the .

The video card installed was I believe a GT120 512MB card. I don't know if this card is faulty or not. I could try it in another basic Intel based PC and see if it shows anything. Or is it hardwired for Apples only?

Depends, this GPU will not work with all PCs, recent Intel PCs do not support CSM anymore and an Apple GT 120 will not work.

I have access to another nvidia card - GTX1050Ti - but I doubt that would work.

What else could I try before I scrap it?

Check the RTC battery voltage? Inspect the CPU tray, test a known working one…
 
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jave808

macrumors member
Original poster
Apr 13, 2023
41
0
Newcastle NSW Australia
Inspect exactly which LED is lit red and act accordingly. It can point out to exact memory slot with faulty RAM stick. Those lights could also point out that maybe someone tried to change CPU(s) and did not tighten CPU cooler properly and because of that CPU(s) do not have proper contact with pins bellow.

But this is the first step, inspect those RED lights. And no, missing of HDD/SSD can't be reason for this behavior.
Hey thank you for replying. There is no RAM installed, apart from one stick at the back of the CPU board. I believe this is an 8-core model (2 CPUs). There is one big heatsink on the left at the front of the case with RAM slots behind it (and one RAM stick), and one big heatsink at the back on the right, with no RAM installed.

I want to get to that RAM stick at the back, but for the life of me I cannot pull out the CPU/RAM board. I have disengaged the 2 locks at the bottom, and even then it still won't budge!
 

jave808

macrumors member
Original poster
Apr 13, 2023
41
0
Newcastle NSW Australia
EFI_DONE LED?
The only LEDs I can see are the ones near the RAM slots on the right hand side, and when I press that diagnosis button (I think that's what it is) on the back board (near the SATA connectors) I get 2 green solid LEDs - no flashing.

Check the RTC battery voltage? Inspect the CPU tray, test a known working one…
I don't have access to a multimeter atm, but I do have plenty of new CR2032 batteries lying around. Is there a trick to getting the old battery out? Do you lever on the spring clip and slide the old battery out?
 

tsialex

Contributor
Jun 13, 2016
13,454
13,601
The only LEDs I can see are the ones near the RAM slots on the right hand side, and when I press that diagnosis button (I think that's what it is) on the back board (near the SATA connectors) I get 2 green solid LEDs - no flashing.

EFI_DONE is one of the LEDS of the DIAG circuit, press the DIAG button with the Mac Pro powered on.

I don't have access to a multimeter atm, but I do have plenty of new CR2032 batteries lying around. Is there a trick to getting the old battery out? Do you lever on the spring clip and slide the old battery out?

Take care and don't move the spring lock too much, you can break it easily.
 

jave808

macrumors member
Original poster
Apr 13, 2023
41
0
Newcastle NSW Australia
EFI_DONE is one of the LEDS of the DIAG circuit, press the DIAG button with the Mac Pro powered on.
Okay, when I do press that DIAG button, I get 2 green LEDs lighting up. What does that mean?

Also, I get two red LEDs on the CPU board - one at the back where the single RAM stick is, and one at the front with no RAM installed.

When I press the DIAG button with the Mac turned off (but still power from the mains to the PSU) I get an orange LED lighting up.

Take care and don't move the spring lock too much, you can break it easily.
Yep, replaced it successfully with a new one. Still the same non-booting issue.
 

tsialex

Contributor
Jun 13, 2016
13,454
13,601
Okay, when I do press that DIAG button, I get 2 green LEDs lighting up. What does that mean?

You need to identify the LEDs, Apple Service Manual around page 28 to 33 have the description.

Also, I get two red LEDs on the CPU board - one at the back where the single RAM stick is, and one at the front with no RAM installed.

Red LED without a DIMM installed is usually a short. Test with a known working CPU tray.

When I press the DIAG button with the Mac turned off (but still power from the mains to the PSU) I get an orange LED lighting up.

Apple Service Manual around page 28 to 33

Yep, replaced it successfully with a new one. Still the same non-booting issue.

Your issue is the CPU tray and not the RTC, but an empty RTC makes the Mac Pro un-bootable, so, you have to be sure that the RTC is working. Elimination game.
 

jave808

macrumors member
Original poster
Apr 13, 2023
41
0
Newcastle NSW Australia
Your issue is the CPU tray and not the RTC, but an empty RTC makes the Mac Pro un-bootable, so, you have to be sure that the RTC is working. Elimination game.
Thank you. I am trying to get the CPU tray out, have undone the two front latches but it still won't pull out. I can move the tray a little bit. Someone has really jammed it in there previously. Is there a trick to removing the CPU tray?
 

jave808

macrumors member
Original poster
Apr 13, 2023
41
0
Newcastle NSW Australia
Thank you. I am trying to get the CPU tray out, have undone the two front latches but it still won't pull out. I can move the tray a little bit. Someone has really jammed it in there previously. Is there a trick to removing the CPU tray?
I got it! I wasn't "undoing" the two front latches far enough. CPU comes out easily now.

I went ahead and bought a 2nd hand working dual CPU tray off a local seller on ebay. That should do the trick.
 

tsialex

Contributor
Jun 13, 2016
13,454
13,601
I got it! I wasn't "undoing" the two front latches far enough. CPU comes out easily now.

Glad that you got it.

I went ahead and bought a 2nd hand working dual CPU tray off a local seller on ebay. That should do the trick.

While everything that you wrote seems to indicate that the CPU tray is defective, you still could have a defective/problematic PSU or backplane.

My advice is always try to buy a barebones working Mac Pro and then test each part of the defective one at a time instead of buying parts piece meal. Seems counterintuitive or even more expensive at first look, but if something else is defective you probably will spent more than a barebones working one.

You can always sell the tested working parts later and recoup or even make money, lot's of people do that.
 

jave808

macrumors member
Original poster
Apr 13, 2023
41
0
Newcastle NSW Australia
My advice is always try to buy a barebones working Mac Pro and then test each part of the defective one at a time instead of buying parts piece meal. Seems counterintuitive or even more expensive at first look, but if something else is defective you probably will spent more than a barebones working one.

You can always sell the tested working parts later and recoup or even make money, lot's of people do that.
Thanks. Yeah I might do that. The CPU tray with 2 CPUs installed wasn't hideously expensive (AUD$255 = US$170) so I'm not too concerned, but I will look around for another Mac Pro 4,1
 

jave808

macrumors member
Original poster
Apr 13, 2023
41
0
Newcastle NSW Australia
Well, the 2nd hand replacement board arrived.

Installed 64GB of DDR3 ECC RAM and inserted the new CPU tray. NO red lights, either with the board or with the RAM sticks.

But still no chime or display through the GT120 video card that was in the Mac when I picked it up.

What do I need to look for now? Video card or something else?

If it is a video card, I have access to a GT1030 (no extra power required), a GTX1060 (needs 6pin PCIe) and an old nvidia Quadro 2000 card. If I need a PCIe power lead from the PSU where would I find it?
 

tsialex

Contributor
Jun 13, 2016
13,454
13,601
Most probable is that you at least have a brick to repair - EFI_DONE is even lit?

You can try to remove the RTC battery and see if it change anything.

My advice of buying a barebones working early-2009 still stands, a lot cheaper than buying parts piecemeal.
 

jave808

macrumors member
Original poster
Apr 13, 2023
41
0
Newcastle NSW Australia
Most probable is that you at least have a brick to repair - EFI_DONE is even lit?

You can try to remove the RTC battery and see if it change anything.

My advice of buying a barebones working early-2009 still stands, a lot cheaper than buying parts piecemeal.
Hey thank you for your reply.

Yes, I think you're correct. EFI_DONE is not lit when powering on. When power is on and I press the DIAG button I get three LEDs light up on the top right of the backboard and only 1 LED lit next to the DIAG button (it is the top of the LED tree).

I'm going to look around for another working 4,1. :)
 

jave808

macrumors member
Original poster
Apr 13, 2023
41
0
Newcastle NSW Australia
UPDATE: I gave the Mac away on Facebook Marketplace. I looked around for another 4,1 but couldn't find one at a realistic price. So I'm now going to sell off the CPU tray through an ebay auction. Might get a bid, might not.
 
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