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NCMcClure

macrumors newbie
Original poster
Feb 12, 2018
12
8
Hey everyone, so I purchased a 2009 4,1 Mac Pro (Dual x5550) on Craigslist a couple weeks ago for $150. Honestly insane deal for how good of condition it's in. I painlessly flashed it to a 5,1, installed High Sierra, upgraded to 32gb of RAM, and installed a GTX 1070. I've had absolutely no problems with it at all until last night. It was sleeping and I went to wake it up by pressing the spacebar on the keyboard and the light on the front of the case just turned off, no noises or anything. It wouldn't boot up at all after that.

So I started troubleshooting. I unplugged the power cord (briefly saw the red diag CPU LEDs flash) for 15 seconds and then plugged it back in (CPU LEDs flashed again, but for a bit longer), tried booting it up but then again nothing happened. No click sounds, absolutely no signs of life. I then removed all HDDs, Optical drives, graphics card, and replaced the RAM with what the Mac Pro originally came with. I tried booting it up and once again nothing happened. I then pressed the DIAG button and I do see the 5V STBY light up.

Nothing I did seemed to fix the problem, so I basically gave up and left the Mac unplugged all night. About 20 hours later (now), I decided I would try and see if it would miraculously turn on, so I plugged the power cable in, pressed the button and the white light on the front of the case turned on and I heard a click... for about a second and then it shut off again. Now nothing I do will turn it on again.

Could someone possibly lead me in the right direction as to what part may be the culprit here? I really don't want to take it to a Mac Pro Specialist here in LA to get it diagnosed, and I certainly don't want to buy a Power Supply on a whim and hope that's the problem. Any help would be greatly appreciated, thanks!
 

TiggrToo

macrumors 601
Aug 24, 2017
4,205
8,838
Unsure if this is of any benefit, however just in case (also unsure if the 2009 differs from the 2007 & 2008)...

Source: https://www.ifixit.com/Guide/iMac+Intel+24-Inch+EMC+2134+and+2211+Diagnostic+LED's/7443

  • LED 1 - Indicates that the trickle voltage from the power supply is detected by the main logic board. This LED will remain ON while the iMac is connected to the AC power. The LED will remain on even when the computer has been shut down or put to sleep. The LED will turn off only if the AC power is disconnected or the power supply is faulty.


  • LED 2 - Indicates that the main logic board has detected proper power from the power supply when the computer is turned on. This LED will be ON when the computer is turned on and the power supply is working correctly.


  • LED 3 - Indicates that the computer and the video card are communicating. This LED will be ON when the computer is communicating properly with the video card. If LEDs 1 and 2 are ON and you heard the startup sound, but LED 3 is OFF, then the video card might be installed incorrectly or need replacement.


  • LED 4 - Indicates that the computer and the LCD display panel are communicating. This LED will be ON when the computer is turned on and video signal is being generated. If the LED is ON and there is no image on the LCD display panel, the LCD display panel or inverter might be installed incorrectly or need replacement.
 

Razzerman

macrumors 6502
Sep 11, 2007
276
172
Hey there,

DId you take out the 1070 and replace with original graphics card that the mac pro came with?
 

NCMcClure

macrumors newbie
Original poster
Feb 12, 2018
12
8
Unsure if this is of any benefit, however just in case (also unsure if the 2009 differs from the 2007 & 2008)...

Source: https://www.ifixit.com/Guide/iMac+Intel+24-Inch+EMC+2134+and+2211+Diagnostic+LED's/7443

Not sure how similar the diagnosis LEDs are from the iMac and Mac Pro, but if they are similar then it would seem as though my power supply is at fault here considering no LEDs are powered on when the power cable is plugged in.

Hey there,

DId you take out the 1070 and replace with original graphics card that the mac pro came with?

Yeah, I tried that but still no dice :/
 

Razzerman

macrumors 6502
Sep 11, 2007
276
172
Whip the hard drive out, and the 1070 and maybe just keep two sticks of ram in. Put the original graphics card in and try & boot then. It won't boot, obviously, but it should come up with the flashing folder (hopefully) - at least that'll show the PS is okay.
 

NCMcClure

macrumors newbie
Original poster
Feb 12, 2018
12
8
Just to preface this answer, my Mac Pro has been unplugged all night up until trying what you just suggested.

So I did as you said, left two sticks of RAM in, replaced the 1070 with the original GPU, and took out all hard drives. I then plugged in the power cable and tried booting it up. It briefly acted as if it was booting up (system fans spun at full speed, along with the GPU fan, and DIAG LEDs lit up) and then stopped. All of the fans stopped, but strangely enough, the OVTMP CPUA red LED stayed lit. Pressing the power button again did nothing to the system, that red LED was stuck like that until I unplugged power cable.

I then waited a minute, plugged the power cable back in, and tried booting again to see if I could replicate that result, but again absolutely nothing happened when pressing the power button, just silence. I snapped a picture of the LED lit up since I had the chance.
 

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Razzerman

macrumors 6502
Sep 11, 2007
276
172
Okay, that picture says a lot..

Taken from the 2009 Mac Pro Techician guide:

"Processor Diagnostic LEDs
The 8-core and quad-core riser boards include a diagnostic LED for each processor that you
can use in troubleshooting processor issues. The following illustrations show the location of
each LED and its associated processor. These error LEDs are normally off. A red illuminated LED
indicates the associated processor may be missing or in overtemp state (PROCHOT).

Troubleshooting CPU Diagnostic LEDs
Determine if the error LED follows the processor heatsink; verify the heatsink is physically
undamaged and properly connected to the processor board, check that adequate thermal
grease is applied, and verify the fan is operating. For 8 core riser boards only: determine if the
error LED follows the processor by swapping processor A and processor B locations."

Also, it could related to the known issue of the Northbridge heatsink clip

https://forums.macrumors.com/threads/cmp-4-1-northbridge-temp-high.1926995/

Hope this helps,

Razzerman
 

NCMcClure

macrumors newbie
Original poster
Feb 12, 2018
12
8
Okay, that picture says a lot..

Taken from the 2009 Mac Pro Techician guide:

"Processor Diagnostic LEDs
The 8-core and quad-core riser boards include a diagnostic LED for each processor that you
can use in troubleshooting processor issues. The following illustrations show the location of
each LED and its associated processor. These error LEDs are normally off. A red illuminated LED
indicates the associated processor may be missing or in overtemp state (PROCHOT).

Troubleshooting CPU Diagnostic LEDs
Determine if the error LED follows the processor heatsink; verify the heatsink is physically
undamaged and properly connected to the processor board, check that adequate thermal
grease is applied, and verify the fan is operating. For 8 core riser boards only: determine if the
error LED follows the processor by swapping processor A and processor B locations."

Also, it could related to the known issue of the Northbridge heatsink clip

https://forums.macrumors.com/threads/cmp-4-1-northbridge-temp-high.1926995/

Hope this helps,

Razzerman

Thanks, Razzerman! I'll definitely check out the riser board along with the Northbridge heatsink when I get home from work later. I hope the Northbridge heatsink is the culprit since that seems like a relatively trivial thing to fix. I'll keep this thread updated with my findings!
 

NCMcClure

macrumors newbie
Original poster
Feb 12, 2018
12
8
So after inspection of my riser board, I couldn't seem to find anything out of order. Northbridge heatsink clips seem to be intact and pretty sturdy, and swapping the CPUs (A -> B and B -> A) didn't seem to change anything. I'm seeing a recurring pattern here though. Every time I try to boot up the Mac after leaving it completely unplugged for 12+ hours, I seem to get some life out of it very briefly (few seconds), but upon trying to boot again after that first sign of life, it goes back to being completely dead. Wouldn't this be a sign of power supply capacitor failure?
 

Razzerman

macrumors 6502
Sep 11, 2007
276
172
Ouch...that's disappointing. Back to square one then :(

You may have to bite the bullet and get a PSU. I'd look at it that if it didn't work, you could resell the PSU for a few bucks less, and not much lost. And if it is the PSU, the machine was a really good price in the first place. Some places might even take the old PSU for refurbishment.
 
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mostafiz28

macrumors member
Feb 16, 2013
49
0
Hi there, just wanted to know whether you could figure out what was wrong with your mac. Though my guess is its a failed PSU, it can be the backplane too. Please keep us informed. Thanks.
 

NCMcClure

macrumors newbie
Original poster
Feb 12, 2018
12
8
Also, take a look at this - sounds a bit similar.

https://discussions.apple.com/thread/7812732

Hi there, just wanted to know whether you could figure out what was wrong with your mac. Though my guess is its a failed PSU, it can be the backplane too. Please keep us informed. Thanks.

So, I finally got around to purchasing a PSU from eBay from a very reputable seller who claims it was only used for a few months in total. While I was trying to remove the screws to get to the current PSU, I completely stripped one of them to the point where it's completely impossible to get it out, the head is practically just a circle. So I went ahead and ordered a screw removal kit on Amazon in order to get it out.

I pretty much gave up at that point and thought "what the hell why not just try to plug in the new PSU to at least see if that's the problem?" (probably what I should have done in the first place). So I removed the current PSU's connector and plugged in the new PSU and still... I get no boot :( The red LEDs blip for a second and the diagnostic button gives me the same yellow 5V STBY LED light. Not too sure what else to do at this point.
 
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Razzerman

macrumors 6502
Sep 11, 2007
276
172
Looks like your best bet is to sell it for spares/repairs, and see if the seller will take back the 'new' psu.

Sorry it hasn't worked out well for you & your machine.
 

mostafiz28

macrumors member
Feb 16, 2013
49
0
So, I finally got around to purchasing a PSU from eBay from a very reputable seller who claims it was only used for a few months in total. While I was trying to remove the screws to get to the current PSU, I completely stripped one of them to the point where it's completely impossible to get it out, the head is practically just a circle. So I went ahead and ordered a screw removal kit on Amazon in order to get it out.

I pretty much gave up at that point and thought "what the hell why not just try to plug in the new PSU to at least see if that's the problem?" (probably what I should have done in the first place). So I removed the current PSU's connector and plugged in the new PSU and still... I get no boot :( The red LEDs blip for a second and the diagnostic button gives me the same yellow 5V STBY LED light. Not too sure what else to do at this point.

If you have an Apple authorised service cernter, try and get it diagnosed. It can be the backplane or the cpu tray. But once you have it pin pointed, it will be easier to fix.
 

NCMcClure

macrumors newbie
Original poster
Feb 12, 2018
12
8
UPDATE: So I just finished moving to a new apartment. This is after having not done anything to the Mac since the last time I posted about unsuccessfully trying a new power supply. I thought "hell why not try to plug it in and see if it powers on?". So I did. And it powered on the moment I plugged in the power cable! I didn't even press the power button. Fans came on normally, hard drives spun up, and I heard the chime sound indicating that it had successfully booted!

I let it run for a few minutes and then proceeded to turn it off and move it to my monitor so I could hopefully get into the system. Sadly, it will no longer boot up again. On the upside though, doesn't this mean there isn't anything wrong with the processor tray, processors, RAM, or power supply? I'm starting to believe it has something to do with the power button at this point if everything booted up properly.
 
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h9826790

macrumors P6
Apr 3, 2014
16,656
8,587
Hong Kong
UPDATE: So I just finished moving to a new apartment. This is after having not done anything to the Mac since the last time I posted about unsuccessfully trying a new power supply. I thought "hell why not try to plug it in and see if it powers on?". So I did. And it powered on the moment I plugged in the power cable! I didn't even press the power button. Fans came on normally, hard drives spun up, and I heard the chime sound indicating that it had successfully booted!

I let it run for a few minutes and then proceeded to turn it off and move it to my monitor so I could hopefully get into the system. Sadly, it will no longer boot up again. On the upside though, doesn't this mean there isn't anything wrong with the processor tray, processors, RAM, or power supply? I'm starting to believe it has something to do with the power button at this point if everything booted up properly.

If you suspect it's the power button. After SMC reset, you can try this.
Screen Shot 2018-04-07 at 18.42.23.png
 

NCMcClure

macrumors newbie
Original poster
Feb 12, 2018
12
8
If you suspect it's the power button. After SMC reset, you can try this. View attachment 757287

So I tried jumping the PWR pads as instructed from the troubleshooting manual and the Mac didn't power on. So it looks like the backplane is the culprit and not the power button. I went ahead and ordered a replacement backplane from dncomputers.ws. Luckily they provide a 30-day return for any reason. I'll keep you guys updated!
 
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NCMcClure

macrumors newbie
Original poster
Feb 12, 2018
12
8
UPDATE: IT'S ALIVE!

So after receiving, and installing, the new backplane, the Mac boots up successfully and I can turn it off... And turn it back on!

I'm now in the process of finally installing High Sierra on my Samsung SM-951 that I received months ago, the night everything stopped working for me.

So I guess if there's anyone out there that has had the exact same troubles as me, I would just bite the bullet on a backplane. That is if you put as little money as I did into acquiring the Mac Pro in the first place. Otherwise it might be a far more difficult pill to swallow.
 

NCMcClure

macrumors newbie
Original poster
Feb 12, 2018
12
8
Lol thanks guys!

So a rather strange development has happened on my end when trying to install MacOS onto my SM951 (MZVPV256HDGL-00000) with my Lycom adapter. I installed the adapter into slot 3 and Disk Utility does in fact detect the drive as an external volume, which from what I've read is normal. I formatted the drive to APFS and started the High Sierra installation process.

Upon finishing the initial installation and rebooting, the Mac just refuses to boot to the drive. Even when I go to the Startup Disk utility in recovery, it shows nothing there, as if it's not detected as a bootable drive. The disk is still detected in Disk Utility and shows ~5gb of used space. I also tried all other PCI-E slots only to get the exact same result. I even tried another NGFF adapter (Silverstone ECM22) that I had laying around and still get the same result.

I'm a bit puzzled by this and I can't seem to find much existing advice on the forums about such a problem. Any tips?
 
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h9826790

macrumors P6
Apr 3, 2014
16,656
8,587
Hong Kong
Lol thanks guys!

So a rather strange development has happened on my end when trying to install MacOS onto my SM951 (MZVPV256HDGL-00000) with my Lycom adapter. I installed the adapter into slot 3 and Disk Utility does in fact detect the drive as an external volume, which from what I've read is normal. I formatted the drive to APFS and started the High Sierra installation process.

Upon finishing the initial installation and rebooting, the Mac just refuses to boot to the drive. Even when I go to the Startup Disk utility in recovery, it shows nothing there, as if it's not detected as a bootable drive. The disk is still detected in Disk Utility and shows ~5gb of used space. I also tried all other PCI-E slots only to get the exact same result. I even tried another NGFF adapter (Silverstone ECM22) that I had laying around and still get the same result.

I'm a bit puzzled by this and I can't seem to find much existing advice on the forums about such a problem. Any tips?

You can't boot from a NVMe SSD
 

NCMcClure

macrumors newbie
Original poster
Feb 12, 2018
12
8
You can't boot from a NVMe SSD

Damn, I totally overlooked that one letter when I placed the order. No wonder I thought I got it for such a good deal on eBay lol looks like I'll be creating a new eBay listing tonight
 
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