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Advice needed... possibly bricked my cMP?!?

Slash-2CPU said:
What's the s-Spec on the X5650's? SLBV3 or Q3xx or Q4xx? It's laser etched onto the heat spreader. If they're Q (qualification samples), then it's a crapshoot.
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SLBV3 on both heat spreaders.

Doesn't make sense... Mojave installed without a hitch just now. I'm currently posting on the cMP running Mojave with the RX 480 and the dual E5520s when this machine literally wouldn't fully boot just hours ago. I'm very curious to see what happens when I clean the X5650 CPUs and apply new thermal paste when I re-install them tomorrow.
 
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tpivette89 said:
I didn't think that was a factor as they were working perfectly until my son halted the Mojave update. It's not like I swapped them out and THEN the system became unresponsive. Didn't seem as though that could possibly be a factor. Why would they have worked for 3 days and suddenly crap out on the 4th?

I will know for sure tomorrow when I can get my hands on some new thermal paste.
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Three days is well within a period of time that any newly-installed hardware can fail, especially because I assume at this point these were used CPUs you purchased. I wouldn't have immediately expected that to be the cause either, but at the same time after the first few troubleshooting steps weren't helping, had I known you just installed new CPUs I would have suggested taking one out and/or swapping back in the original ones.

I'm not bagging on you, just saying that when troubleshooting it's always helpful to know about any recent hardware change.

EDIT: But by all means, please have tsialex look at your bootrom dump, especially if your cMP ever ran Windows 10. Bootrom corruption can cause all sorts of weird boot issues.
 
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bookemdano said:
Three days is well within a period of time that any newly-installed hardware can fail, especially because I assume at this point these were used CPUs you purchased. I wouldn't have immediately expected that to be the cause either, but at the same time after the first few troubleshooting steps weren't helping, had I known you just installed new CPUs I would have suggested taking one out and/or swapping back in the original ones.

I'm not bagging on you, just saying that when troubleshooting it's always helpful to know about any recent hardware change.
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Sorry about that, I guess it's my fault because I just would have never thought these CPUs were the culprit since they were working just fine beforehand. The problem occurred when my son halted the install of Mojave, so I was more focused on that than anything else. I guess I could've attributed the malfunction to the RX 480, cause it too, was just swapped that day (although that turned out to not be the case). Troubleshooting is tough, that's for sure.

All will be revealed tomorrow when I get my hands on some new thermal paste... unless the computer acts normally when I swap CPUs. Then I won't know what to think...
 
Could be a damaged/dirty/corroded/burned contact pad on the CPU. Try cleaning the contacts on the bottom of the CPU with isopropyl alcohol and a q-tip or cotton pad.

Most thermal pastes are insulators. A small bit on the bottom of the CPU in the wrong spot will prevent a good connection.
 
So I reinstalled the dual X5650s again today after picking up some thermal paste. Slid the tray in and powered the machine on. Was greeted with the chime, but nothing on the screen (like it was doing before). So I removed one processor and tried again... same results. Swapped that CPU out with the 2nd one, and the machine booted!

So one of the processors apparently went bad. Luckily these things are dirt cheap ($15 shipped) and I will be ordering another one to replace the defective unit.
 
tsialex said:
Try to load a Linux Rescue-CD, if loads sucessfully, we can reflash the BootROM using flashrom.

Gparted live cd is the one that people flashed Mac Pro BootROMs.
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Can you disable SIP from Linux or it is not important for flashing from Linux?
 
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tsialex said:
If I remember correctly, Linux subsystem don't have low level access to the hardware, but test it.
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On my Laptop I get this:
Code: 
sudo flashrom -r test -p internal
flashrom v0.9.9-r1954 on Linux 4.4.0-17763-Microsoft (x86_64)
flashrom is free software, get the source code at https://flashrom.org

Calibrating delay loop... OK.
ERROR: Could not get I/O privileges (Function not implemented).
You need to be root.
Error: Programmer initialization failed.
 
I'm having a somewhat similar problem.

I updated my 5,1 to dual x5690's about two weeks ago and it's been working well. Last week I put in a Samsung 970 evo NVME in a PCI card and ordered an RX 580 when I realized I needed to flash the bios to boot. The RX 580 arrived earlier today, I installed it and it booted 13.6. I installed Mojave and the BIOS update completed normally and I was at a desktop with Mojave installed and booted on the NVME drive.

Dropbox was indexing (really high CPU usage temps were ~80c and ~64c) and the I ran a Cinebench to see what the score was and the circuit breaker flipped. These breakers flip if a spark is detected on the line, it wasn't overloaded. So ... ¯\_(シ)_/¯

Now the computer won't boot. I think either the new 6-8pin power cables or the RX 580 fried something :/

I removed everything and went back to the default Radeon 5770 and it still won't get to the Apple logo. When I take out all drives, I get a ? Folder flashing after 30 sec but it won't do anything with a drive in. Reset PRAM and SMC, tried recovery and tried verbose boot - nothing.

I get the start up chime and then just stuck at a grey screen.

The only thing I can think to do is to switch back to the original processors.

I did look over the exposed circuit boards and didn't see any black marks or signs of damage.


---

After hours or swapping parts around and trying to boot from a Linux live USB image (wouldn't find it as a boot device), I tried accessing my old SSD system drive (which I had been trying to get the cMP to boot from) and it wouldn't mount on my MacBook. Whatever happened must fried it. It was near the 6-pin to 8-pin power adapter for the RX 580 and I'm convinced there was a spark.

I put the NVME drive back in and it booted just fine. It's all back together minus the RX 580, I'll let it run for a day or two before I try putting it back in.
 
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