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MP 1,1-5,1 cMP 5,1 no chime, black screen, no POST
- Thread starter nkinne
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There are 2 version's of the CH341a, both work well but the early version has too much voltage to the chips. Some SPI chips are sensitive to voltage. I purchased 20 SPI flash chips from a reliable source and have Flashed 6 reconstructed Rom's from tsialex and replaced them on 6 back plains with out one failure, all work perfectly.
The 2 versions are here, the one below is the older version with a voltage mod i did so it's only 3.3v the newer one has a voltage switch, with 7v 5v + 3.3v both are different layout PCB's but both work as they should.
I always use a PC to flash my SPI chips, a lenovo think station, Flash SPI, verify the flash then hot air remove old SPI from back plain and fit new SPI. Not because the old one failed but its been written too for the last 10 + years and when the new one is fitted with reconstructed boot rom from Alex its like the Mac pro 5.1's first ever boot just like from factory new.
I would say buying SPI flash chips from a reliable source is always the best policy. the SPI flash chips i use are MX25L3205D
The 2 versions are here, the one below is the older version with a voltage mod i did so it's only 3.3v the newer one has a voltage switch, with 7v 5v + 3.3v both are different layout PCB's but both work as they should.
I always use a PC to flash my SPI chips, a lenovo think station, Flash SPI, verify the flash then hot air remove old SPI from back plain and fit new SPI. Not because the old one failed but its been written too for the last 10 + years and when the new one is fitted with reconstructed boot rom from Alex its like the Mac pro 5.1's first ever boot just like from factory new.
I would say buying SPI flash chips from a reliable source is always the best policy. the SPI flash chips i use are MX25L3205D
Ok. Flash chip was successfully programmed. All that had to be done was to jump on a Windows PC. Neoprogrammer was used and chip was read/erased/written and varifiedx3 in just a few minutes. I'm not sure what was the problem with Flashrom and my MBP. Regardless, that part is done.
New issue:
Applied new flash memory chip to backplane, buttoned everything up then powered up. The PSU went clickity clackity like crazy while the CPU tray and backplane are lit up like a Christmas tree. Fans are going nuts as the power flicks off and on repeatedly. Somethings wrong.
Removed power, and referred to the Apple Technician Guide Service Manual. I stripped the machine down to the minimum.
When plugged in the 5v STBY lights up. I then begin the process of adding parts and attempting power cycle. Only a couple of times I would get the click of PSU and some lights momentarily. But it won't stay on the way it first did when it was freaking out. So it largely does nothing now.
The Tech manual was followed to a t as far as what was relevant to my current issue. The backplane seems to be toast. About time to buy a new backplane?
New issue:
Applied new flash memory chip to backplane, buttoned everything up then powered up. The PSU went clickity clackity like crazy while the CPU tray and backplane are lit up like a Christmas tree. Fans are going nuts as the power flicks off and on repeatedly. Somethings wrong.
Removed power, and referred to the Apple Technician Guide Service Manual. I stripped the machine down to the minimum.
When plugged in the 5v STBY lights up. I then begin the process of adding parts and attempting power cycle. Only a couple of times I would get the click of PSU and some lights momentarily. But it won't stay on the way it first did when it was freaking out. So it largely does nothing now.
The Tech manual was followed to a t as far as what was relevant to my current issue. The backplane seems to be toast. About time to buy a new backplane?
It certainly seemed to do the trick for me. Thought I had a batch full of faulty chips or a bad programmer. Weird.
I take it you did put the SPI flash chip on the back plain the right way round? if so then it seems by your description of PSU clicking like crazy that the PSU is bad. you need to try a good PSU before condemning the back plain. Also make sure the BR2032 battery has at least 3v in it.
Can you take a picture of your SPI chip on logic board and post it here?
Can you take a picture of your SPI chip on logic board and post it here?
Before buying anything, try to confirm that your CPU tray and PSU still works with another Mac Pro. PSUs fail a lot after 12+ years, specially the ACBel made. CPU trays fail less, but you should confirm that everything else besides the backplane is working or you will start to spend a lot very fast.
SPI is the right way around, yes. The battery is new. Checked the old one just to see, and it was fine, too. I can post pics later when I get a chance.
I, unfortunately, don't have access to another Mac Pro. So I'll have to find an alternative way to check the health of the CPU tray and PSU. When checking if the backplane was receiving power via the DIAG button, the 5V lights up just fine and, occasionally, the PSU PWROK light will also light. Not sure if that's important or very telling or what.
Here is an exact example of what is happening to me. The OP has a couple of videos that are identical to what I was experiencing. https://forums.macrumors.com/threads/macpro-5-1-power-issue.2231091/
I've written this before, without access to a LITTLEFRANK interface and the Apple internal diagnostic software/server, it's too complex to diagnose a Mac Pro without testing each part with a known working Mac Pro.
Even people like me or @Macschrauber that have ten+ years of experience and know exactly where to look prefer to have a test mule just to save time with the diagnostic process.
Buy the cheapest working early-2009 to mid-2012 Mac Pro and fully diagnose yours, will be cheaper that buying a backplane/PSU/CPU tray. You can sell the confirmed working parts and in the end make more money than what you spent.
Even people like me or @Macschrauber that have ten+ years of experience and know exactly where to look prefer to have a test mule just to save time with the diagnostic process.
Buy the cheapest working early-2009 to mid-2012 Mac Pro and fully diagnose yours, will be cheaper that buying a backplane/PSU/CPU tray. You can sell the confirmed working parts and in the end make more money than what you spent.
I'm at a bit of a loss with this machine. Received a new backplane. It seems to work just fine. There was definitely something up with the previous one. The machine powers up great. However, still no POST. My process so far to trace the problem has been:
- Install new backplane and only basic components to start.
- Install stock CPU Xeon 5500s in case new backplane hasn't been previously upgraded to 5,1.
- Prepared El Capitan boot usb ahead of time as the HDDs attached to machine are either Mojave, Big Sur or Win10.
- Cleaned everything really well.
Results:
- No POST
- DIAG lights lit:
PSU PWROK (solid green)
5V STBY (amber)
SYS PG (solid green)
EFI DONE (solid green)
GPU OK (solid green)
- Fans spin normally
- No red LED on CPU board accept briefly on powerup.
- Tried tightening/loosening cpu heatsinks in variations in case they were too tight or vice versa.
- Removed one CPU in A than B with all but one RAM stick, swapped CPU's and RAM in all combinations.
Still nothing. Would it be strange for both the backplane and CPU tray to go bad at the same time? Or am I missing something here?
As much as I would rather take @tsialex advice to simply buy the cheapest complete '09-'12 machine I can find and test with that, it's still more expensive than buying the parts I suspect are faulty individually.
- Install new backplane and only basic components to start.
- Install stock CPU Xeon 5500s in case new backplane hasn't been previously upgraded to 5,1.
- Prepared El Capitan boot usb ahead of time as the HDDs attached to machine are either Mojave, Big Sur or Win10.
- Cleaned everything really well.
Results:
- No POST
- DIAG lights lit:
PSU PWROK (solid green)
5V STBY (amber)
SYS PG (solid green)
EFI DONE (solid green)
GPU OK (solid green)
- Fans spin normally
- No red LED on CPU board accept briefly on powerup.
- Tried tightening/loosening cpu heatsinks in variations in case they were too tight or vice versa.
- Removed one CPU in A than B with all but one RAM stick, swapped CPU's and RAM in all combinations.
Still nothing. Would it be strange for both the backplane and CPU tray to go bad at the same time? Or am I missing something here?
As much as I would rather take @tsialex advice to simply buy the cheapest complete '09-'12 machine I can find and test with that, it's still more expensive than buying the parts I suspect are faulty individually.
A defective PSU can burn the backplane and the CPU tray, this wouldn't be the first time this happens.
Now you have to buy a CPU tray/PSU to test yours.
One thing that I learned a long time ago, it's so much easier to have a test mule and diagnose each part separately. Like I wrote to you before, you can buy the cheapest confirmed working early-2009 to mid-2012 that you can find and then test the parts of your defective Mac Pro one by one.
Guess I'll have to be patient and keep an eye out for a complete machine for an acceptable price. Thanks for all the advice.
Another thing, since you don't have a test PSU, take the cover of your PSU and inspect for any bulged caps, pay attention to the smaller caps, the big ones usually don't fail.
If it's a ACBel made one, it's very common to have bulged caps near the primary, I had to replace caps from all my ACBel PSUs.
If it's a ACBel made one, it's very common to have bulged caps near the primary, I had to replace caps from all my ACBel PSUs.
I have no way to know if it's been near an ocean environment. It's definitely not now. It was very clean when I bought it last year– no corrosion or anything of the sort.
It works just fine as far as I know.
Any of the exposed pads over the backplane or the CPU tray are blackened? The CPU tray usually dies before the with backplane Mac Pros that are affected by ocean air corrosion.
One place easy to inspect are the pads for the diagnostic switches that are not installed over the diagnostic circuit of the production backplanes. The pads become blackish overtime on the Mac Pros affected by ocean air corrosion.
They all look clear–no discoloring (on the old backplane and CPU tray). Funny enough, the new backplane does have a bit of the black coloring on the said pads.
No bulged caps. Everything looks great visually. It was a little dusty so I took care of that. Other than a little dust the thing looks new.
Out of curiosity, can matching year (2009-2012) backplane and CPU tray be transplanted to my 2009? Meaning if I find a 2010 backplane and a 2010 CPU tray could they be used together with my current 2009 case (PSU, front board, etc.) without issue?
If the SMC version of the backplane/CPU tray is the same, yes. You can install a mid-2010/mid-2012 CPU tray/backplane to your early-2009 case.
