Mac Pro 5,1 Dual Processor Upgrade Problem

[mpguy2010]

Hey forum members! Long time lurker but first time poster as I'm having an issue with a single processor to dual processor upgrade to my genuine 5,1 Mac Pro. The initial configuration was a stone stock 2.8GHz quad core with the exception I installed 32 GB RAM. Other than the RAM it's stone stock. No aftermarket GPUs, hard drives, or anything. Just the memory. Here's the config:

https://everymac.com/systems/apple/mac_pro/specs/mac-pro-quad-core-2.8-mid-2010-nehalem-specs.html

On Ebay I was able to locate a dual processor tray with dual X5650 processors and 8GB of RAM. When I swapped the single tray for the dual tray the system no longer boots. The monitor doesn't receive a signal, I don't hear the boot chime, I do not hear any disk activity, and the fans spin normally (they do not spin to full speed).

I've read the advice in this forum and pulled each CPU and tested individually in the A socket. I've installed the RAM per Apple's guidelines for four modules and, just for the heck of it, moved them around to various other locations. I even swapped in the known good RAM from the single CPU board. No matter what combination I try the result is always as described above.

I recall reading someone mentioning they had swapped in a dual CPU tray and their system failed to work. I think the problem ended up being the CPU tray was at an older version (of what, I do not recall). I do not know if these are the original CPUs which were installed in the tray (Apple does ship such a configuration for the 2012 model Mac Pro so original would be a reasonable assumption).

A single LED lights up next to the #4 DIMM, the other three remain off. I am unable to see the motherboard LEDs as they're blocked by the B CPU heatsink.

Any ideas what to try? I'd hate to have to return the tray as it was a decent buy.

 

[tpivette89]

Have you tried putting your old CPU in the new tray (socket A only)? Or perhaps, try each of the individual new CPUs that came with the dual tray in your single tray to see if they are good?

Keep RAM to a minimum just for testing purposes... use only 1 stick of your old, known good RAM.

 

[handheldgames]

Hey forum members! Long time lurker but first time poster as I'm having an issue with a single processor to dual processor upgrade to my genuine 5,1 Mac Pro. The initial configuration was a stone stock 2.8GHz quad core with the exception I installed 32 GB RAM. Other than the RAM it's stone stock. No aftermarket GPUs, hard drives, or anything. Just the memory. Here's the config:

https://everymac.com/systems/apple/mac_pro/specs/mac-pro-quad-core-2.8-mid-2010-nehalem-specs.html

On Ebay I was able to locate a dual processor tray with dual X5650 processors and 8GB of RAM. When I swapped the single tray for the dual tray the system no longer boots. The monitor doesn't receive a signal, I don't hear the boot chime, I do not hear any disk activity, and the fans spin normally (they do not spin to full speed).

I've read the advice in this forum and pulled each CPU and tested individually in the A socket. I've installed the RAM per Apple's guidelines for four modules and, just for the heck of it, moved them around to various other locations. I even swapped in the known good RAM from the single CPU board. No matter what combination I try the result is always as described above.

I recall reading someone mentioning they had swapped in a dual CPU tray and their system failed to work. I think the problem ended up being the CPU tray was at an older version (of what, I do not recall). I do not know if these are the original CPUs which were installed in the tray (Apple does ship such a configuration for the 2012 model Mac Pro so original would be a reasonable assumption).

A single LED lights up next to the #4 DIMM, the other three remain off. I am unable to see the motherboard LEDs as they're blocked by the B CPU heatsink.

Any ideas what to try? I'd hate to have to return the tray as it was a decent buy.

Use your old ram, you know it works.
With your new tray, reduce your ram to slots 1-2-3 on CPUA.
These are the only slots you can see when the tray is inserted.
Attempt to boot.
If you do not hear a chime, there is probably something wrong with your new tray.
Good luck.

 

[justinkr]

It’s probably the heat sink. Remove the heat sink and readjust the bolts. The ebay seller might’ve tight it too hard or too loose. When I upgraded my 8 cores to 12 cores and had the same problem and after I did all the adjustments it boot up and work. But make sure you adjust the A heat sink first and if it boot install the B. But if it doesn’t boot the. Readjust the bolts on the A until it boot.

 

[mpguy2010]

Have you tried putting your old CPU in the new tray (socket A only)? Or perhaps, try each of the individual new CPUs that came with the dual tray in your single tray to see if they are good?

Keep RAM to a minimum just for testing purposes... use only 1 stick of your old, known good RAM.

I had not performed this testing at the time of my initial post however I did perform it later. The dual CPU tray, when the CPU from my single tray was installed, failed to function as described in my initial post. One of the X5650 functioned fine in my single CPU tray. I didn't see any point in attempting to try the second X5650 CPU.

I spent some time cleaning the tray (it had a little grunge on it), blowing out the sockets (CPU and memory) with compressed air, and nothing worked. As I originally thought the dual CPU tray is non-functioning. I've reached out to the seller to see if they have another dual CPU tray they'd be willing to exchange with me. If not it looks as if I will have to return it for a refund.