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dontpokebearz

macrumors regular
Original poster
Feb 16, 2018
155
108
Maine
Hi all. Ive finally upgraded my processors to a pair of X5680’s. So far... it hasn’t gone well. The first pair, only one worked. Bought another.
Now, after getting the replacement and ensuring both processors work - the Mac won’t post.

Symptoms:

Computer turns on and fans spin up normally. LEDs near the processors sockets flash quickly as they should. From there, the computer doesn’t post.

Here’s what I’ve done:

1. Tried both processors in socket A. Running individually, the computer will post.
2. inspected Socket B for bent pins. I’ve found one or two, and as far as I can tell I’ve fixed them.
3. When both processors are running I do not get any error LEDs.
4. Diagnostic LEDs read normal, except for GPU OK flashing. I can’t find what this means.
5. SMC reset multiple times. RTC reset.
6. PRAM reset when running single socket. If the computer does not post, I don’t think you can reset PRAM.

has anyone run into this, I’ve tried everything I can think of. At this point I’m ready to turn in the towel and build a PC.

Here’s a video of diagnostic LEDs:

Edit: My Mac Pro is a 4,1 flashed to 5,1 running BootROM version 144.X.X.X / GPU: RX580 / I delidded both processors.
 
Last edited:
Gpu ok flashing is in my experience a problem with the cpu board.



is that 4,1 or 5,1 ?

bet for 4,1 as cpu pins are bent.
 
It’s a 4,1 flashed.
I’m also wondering if it’s related to the thermal pad on socket B. They are quite depressed and the heat sink doesn’t want to naturally sit flat. There’s a lot of play.
 
post pictures of the cpus, how the cpus are delidded and mounted. There shouldnt be any play.

I'm not sure it's an issue of how they are seated. I've installed the old E5560 processors and the computer will post immediately. MacOS reports dual processors.

So it can't be the daughter board? Is there a piece of this puzzle that I'm missing? I have a 4,1 flashed to a 5,1 running Mojave. Boot ROM 144. Is there another step I have to take?
 
Did you delid your CPUs? When I first upgraded my CPUs I tried them first without delidding and had similar issues. I suspect they weren't fully seated and the lids weren't perfectly parallel to the contacts causing some pins to not fully connect. After delidding them, the heatsinks screwed down rock solid and everything worked fine.
 
with barely no information what the TS did exactly no one can help.

He/she even gave the most important information (its a 4.1 not a 5.1) after asking for it.
 
with barely no information what the TS did exactly no one can help.

He/she even gave the most important information (its a 4.1 not a 5.1) after asking for it.
I'll edit my original post to clarify it's a 4,1 flashed to 5,1.

I'm not sure how you're saying I gave next no information on what I did, what did I miss in the original post?
 
Did you delid your CPUs? When I first upgraded my CPUs I tried them first without delidding and had similar issues. I suspect they weren't fully seated and the lids weren't perfectly parallel to the contacts causing some pins to not fully connect. After delidding them, the heatsinks screwed down rock solid and everything worked fine.

I did delid my CPU's. I did not have a vice, so I used the razer blad technique.

Did you screw your heat sinks down fully until there is no more room to screw?
 
I did delid my CPU's. I did not have a vice, so I used the razer blad technique.

Did you screw your heat sinks down fully until there is no more room to screw?
Yes, you should follow a cross pattern from one corner to the the opposite diagonal corner to make sure each heatsink is tightened evenly in all four corners. It's about 7 to 8 turns for each screw until the slightest resistance. Then turn each one approximately another 1/4 to 1/2 turn until they won't turn anymore, but only finger tight. It was obvious when the screws were fully tight and there was no play whatsoever.
 
The die must be polished, the black seal cut down to barely not visible and the spacers mounted.

I do that every time and fasten the screws with normal torque.

dont do this if one of the circumstances above do not match. If so the construction is too high and it will do too much pressure to the socket and will do damage.

thats why I wanted pix.
 
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