MP 1,1-5,1 Apple Mac Pro 5.1 2010 boot fault & Apple Cinema Display 30" flicker fault diagnosis

[sjmmacrumors]

Dear MacRumors Forums members

Following pre-owned system purchased 2019, without drives.

- Apple Mac Pro 5.1 2010 6 Core 3.33GHz 16GB RAM (5.1, not a flashed 4.1)

- ATI Radeon HD5870 GPU
- 
Apple Cinema Display 30" monitor with Apple Mac power adapter

Sourced drive parts following, all pre-owned, and assembled.

- Angelbird Wings PX1 M.2 NVMe PCIe SSD adapter

- Samsung MZHOV512HDGL SSD OS drive
- 
Seagate Barracuda 1TB SATA HD storage drive

Configured SSD into two volumes, Apple Mac OS X 10.6.8 on one volume / no OS on other volume. Loaded OS X 10.6.8 Snow Leopard from original Apple CD. Intention to load more recent MacOS on second volume in future.

AOK for several months, then weeks or months between each, the following faults have arisen:

1. Apple white iMac plastic keyboard stopped working from Apple Cinema Display powered USB port. Works fine from Mac Pro powered USB ports

2. Apple Cinema Display 30"
- Flicker immediately after boot (full black screen)
- Settle ten minutes, then flicker again, then finally settle with protracted use
- No response to Apple Magic Mouse or keyboard to wake from sleep
- Flickering can be resolved by unplugging power lead from Cinema Display power adapter momentarily, then plugging back in

3. Booting issues

- Turn power switch on, light illuminates, optical drive engages, fan starts, PCIe SSD adapter illuminates, HD noise may or may not occur, no boot chime, hard reset
- Usually have to go through this cycle anywhere from 6-12 times before boot chime sounds and OS X login appears on Cinema Display. Which then goes through its flickering regime
- If machine left on overnight, sometimes it will wake for login, other times it will switch off overnight and require rebooting
- Occasionally, certain tasks will cause the Cinema Display to switch off
- Once it boots the Mac Pro itself is fine, but the Cinema Display will be unstable until ten-fifteen minutes have elapsed with multiple replugging of the power adapter
- Today I am getting a light flicker at all times, so am worried even worse things are afoot

PRAM and SMC resets have no effect. The battery has been changed. Dust has been cleaned out. Disc repair performed, no issues. OS X reloaded, no change.

Thanks in advance for any inspired advice on potential source(s) of these problems.


Regards

SJM

 

[KeesMacPro]

Hi

I would do the following:
-test if the issue occurs with a different monitor and/or test the monitor on another computer
-test if the issue occurs with a different GPU and/or test the GPU in another computer

 

[sjmmacrumors]

Good idea thank you. Any other suggestions welcome from forum users too, e.g. could these problems be symptomatic of a failing backplane board, or power supply unit?

 

[sjmmacrumors]

Follow up:

1. Ran Mac OS X hardware test (extended version), result: no problems found

2. Plugged Mac Cinema Display 30" into 2006 Macbook Pro laptop running on original OS X 10.5.8 and booted. Cinema Display activates at MacBook Pro login, appears to be stable.

So unknown issue(s) appear to be contained within the Mac Pro 5.1

 

[KeesMacPro]

I'd test the screen connected to your MBP leaving it on for a few hours , multiple powering on and off , wake /sleep tests etc.
If all works fine, I'd test the GPU.