MP 1,1-5,1 Mac Pro 5.1 Boot Failure After Windows 11 Attempt

[chodjo]

Hello everyone,

I've always been a silent observer on this forum, but unfortunately, my first post is a cry for help. I'm unsure about what's gone wrong with my cMP, and I desperately need assistance.

To pursue my dream of a home studio, I bought a Mac Pro 5.1, upgraded the processors, expanded the RAM to 96GB, and added an RX580. It was a joy to use until I encountered issues trying to run Big Sur with my Firewire audio interface. I attempted OCLP, but it wouldn't boot with the card connected. So, I tried Martin LO's OpenCore version. I installed High Sierra with a GPU that allowed a boot screen, then switched to RX580, upgraded to Mojave, and attempted the leap to Big Sur. The problem arose when installing Martin LO's OpenCore; it allowed access to Mojave but consistently froze. I noticed the RX580 fan wasn't spinning with this OpenCore version, leading me to suspect it had been used in mining and needed a BIOS flash. Using a Windows 11 USB drive and via OpenCore EFI, I installed windows on a secondary SSD (Mojave was on an NVMe). While in Windows 11, I noticed slow internet speed (maybe this info helps), likely due to drivers, but I didn't spend much time there.

I didn't flash the RX580 BIOS, as it appeared to be the standard version, although I encountered a strange error where GPU-Z initially recognized the BIOS, then stopped, preventing me from flashing it.

This morning, after restarting, OpenCore shows up. Mojave fails to start, so I decide to reinstall High Sierra, to start again all the process. When changing the graphics card to install High Sierra, a routine I've done countless times, the computer fails to start properly. I hear mechanical noises 2-3 times (superdrive noise), but the power button doesn't light up, and there's nothing on the screen. I've tried unplugging, reconnecting, and testing with different GPUs, but the result is always the same.

I'm now considering that I may have unintentionally corrupted the BootROM while in Windows. It's challenging to troubleshoot without another nearby cMP to analyze piece by piece.

I'm reaching out for help to determine if I may have bricked the Mac Pro, if the PSU failed, if the motherboard is damaged, or if there's another issue. For additional information, when connecting the ATI 5770, the fan spins slowly, but with the RX580, the fan doesn't spin at all. Regarding the BootROM version, it was 144.0.0.0. I've disconnected all devices except the graphics card (including the SuperDrive) and removed the battery, but the screen still shows nothing. There's no power light, but the GPU fan spins.

Any insights or guidance would be immensely appreciated.

Thank you in advance.

 

[chodjo]

Hello everyone!

I wanted to share an update on my situation. After removing the SuperDrive and conducting some additional tests, I noticed that the PSU fan is not spinning. Could this be the underlying problem? I appreciate any guidance you can provide on how to address this issue. Any suggestions for possible solutions or steps to take?

Thanks in advance for your help!

 

[haralds]

How did you start Windows 11? If it is using UEFI boot instead of legacy BIOS, it can damage your NVRAM. I would not use it. If you do, only boot under OC or OCLP.
I would try this:
- Remove all drives but the one with Mojave, which is natively supported
- Do an SMC reset. (unplug, wait 30 sec, plug in, wait 10s before boot.)
- Do three PRAM resets in a row (Cmd-Opt-P-R on start) to attempt to build NVRAM.
You will not see a boot menu with the unflashed card, but if Mojave is the only OS, the system should boot into that. Once in Mojave, the card should be supported.
I have been very happy with OCLP, which is now on 1.2.1 or 1.3 nightly builds. I was running Monterey with my flashed RX-580 until Logic Pro upgraded requiring Ventura or Sonoma.
- I always have a disk with Mojave and BootCamp Windows 10 - strictly "legal."
- I also have a full config of DosDude patched Catalina as a base config to clone and upgrade. I have an upgraded WiFi/BLE card, so I have full continuity with SIP enabled after patching some config plists.
- I currently also have fully configured and updated installations of Monterey, Ventura, and Sonoma.
Never delete the Mojave install as a goto in case of trouble. I also learned to keep older installs around until OCLP is fully settled. Sonoma is not yet stable on OCLP. Ventura works, but Monterey is bulletproof.

If you are not experienced and need to run systems past Catalina, OCLP is much easier than OC. I am quite technical, but I got tired of fiddling with OC configs.

Good luck.

 

[chodjo]

Hi @haralds,

First of all, thansk for your answer. Ireally appreciate the help. As I was using a RX580, I used OC to install windows 11 via USB.

I have tried all you mentioned, but no change. Computer makes sounds when turned on, but status light wont turn on, and nothing is shown in screen. So, I dont have front panel power/sleep LED working.

I've read the Apple technician guide, and will try this weekend the "Minimum Configuration Testing" to see if I can find out whats the issue in the Mac Pro.

Thanks !

 

[chodjo]

So, an update.

PSU is not the issue as I could get a functioning 2009 one, and still had same issues. I changed CPUs to old ones, and RAM to old RAM. Not 100% sure, but I guess the issue is on the backplane board.

Any recommendations other than buying a new one?

Thanks in advance

 

[John Fu]

Hello, have you tried to use OClP to create a bootable USB, try to use it as a boot-up to see what happens?

 

[chodjo]

Hi @John Fu,

Thanks a lot for your help. I managed to fix my mac pro today by replacing backplane board.

So this issue seems closed

 

[Macschrauber]

Take care of the bootrom, maybe Uefi Windows was in play.

The replaced backplane has another bootrom of course.

Dont boot uefi Windows without nvram protection. Test it from time to time. I made a tool for backing up and analysing the bootrom and the NVRAM whats stored in it. Link in the signature.