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MP 1,1-5,1 MacPro 4,1 dual processor upgrade problem x5680 CPU’s

A

ArchStudent

macrumors newbie
Original poster
Jan 31, 2020
15
1
Hello,

I am hoping someone can help as this problem has me scratching my head.

I have a dual processor Mac Pro 4,1 that originally had dual e5520 CPU’s.

I have updated the firmware (and rom) to make it a 5,1. I have installed two de-lidded x5680 CPU’s. System booted up fine with original dual CPU’s.

i have been very careful with the sockets to ensure there are no bent pins, none! Checked meticulously with a magnifying glass.

Both new x5680 CPU’s work in Socket A, with one 16GB sodimm, but, when I install the second CPU in Socket B the system comes on without boot chime and fans running full speed, like warp speed! From reading, I know that is a symptom of CPU-B not being installed properly.

I have adjusted the screw pressure for CPU-B and even had the system come on but just show that it only has one CPU in the system.

I have modified CPU-B’s heat sink fan connector to properly seat itself, and now the system turns on, still without a chime or boot screen, BUT, then fans do not come on at warp speed. It sounds normal now... I feel I am close, just unsure if CPU-B need a little less tightening.

Since the CPU’s are de-lidded all that I used was the original CPU’s plastic spacers and tightening to just hand tight, no over tightening.

I have switched back to the original e5520 CPU’s and the system boots up without a problem.

I switched back to the new x5680 CPU’s and same issue I have described as above persists. I have tested both x5680 CPU’s in socket-A one at a time and they boot up without a hitch. I have run some cpu benchmarks for an hour with each single x5680... no issues. When I put a second x5680 cpu in socket B, same issue as described above happens.

For now I have re-installed the original CPU’s and the only thing I can think of is that the processor board does not like the higher wattage x5680’s.

I may purchase x5675 CPU’s since they are nearly identical in power consumption to the original CPU’s. That is the only thing I can think of.

Any tips or guidance would be appreciated for those that have updated their dual MP de-lidded CPU’s. I have used the search function, read posts with some depressing results where people gave up, and also read a tonne of posts on here, Facebook forums, Netkas, Etc.

This one is driving me batty!

Thanks!
 
Please define type?

They are both x5680’s

The only difference on them is the batch / finished process order number on the original IHS’s.

thank you :)
 
Last edited:
try reseting the PRAM when you install the new processors.

I once bought a dual CPU 5.1 mac pro from a design agency, they were selling it really cheap for spares or repair because it wouldn't boot.

All I did was cmd+opt+p+r on startup and it burst into life!
 
krakman said:
try reseting the PRAM when you install the new processors.

I once bought a dual CPU 5.1 mac pro from a design agency, they were selling it really cheap for spares or repair because it wouldn't boot.

All I did was cmd+opt+p+r on startup and it burst into life!
Click to expand...

I did that several times. Even when it would only let me boot in to the system with one Of the new CPU’s installed. Made no difference when I added the second new CPU (either new x5680 CPU’s work in socket A) the system would either not get past turning on with no post test chime and running quietly or power on again with no post test chime and then have fans run at full speed.

lone interesting observation to note, CPU B never has the heat sink fan get warm, while cpu A heats up normally.

CPU-B’s heat sink fan has power as the little fan inside the hsf is running,but it is like the system believes that it is only a one cpu system with both X5680’s installed.

thank you
 
Have you tried putting the cpus together flat on table to see if there is any distortion or size difference?

Perhaps try pressing the reset button next to the coin battery holder? Or take the battery out for a few mins.

Its often recommended to reset the PRAM 3 time in a row.

I presume you have updated the boot rom firmware what version are you running? The latest is 144.0.0.

What version OSX are you running?
 
krakman said:
Have you tried putting the cpus together flat on table to see if there is any distortion or size difference?

Perhaps try pressing the reset button next to the coin battery holder? Or take the battery out for a few mins.

Its often recommended to reset the PRAM 3 time in a row.

I presume you have updated the boot rom firmware what version are you running? The latest is 144.0.0.

What version OSX are you running?
Click to expand...

I did in fact replace the cmos battery with a brand new one. I unplugged the machine, and pressed the power button, and then I removed the cmos battery and held the power button down to discharge everything.

The CPU’s I de-lidded myself and there is no size discrepancy between them height wise.

PRAM has been reset three times in a row as well.

Currently on High Sierra with BIOS version MP51.0089.B00

SMC Version 1.39f5 for both system and processor tray

Presently updating to the latest bios (just installing a Gigabyte Windforce R9 280x with mac EFI to allow the update).

it is the weirdest thing, but who knows, a bios update may potentially resolve this issue.
 
Well it seems that I finally found an answer from a post I didn’t see until just now! Go figure.
The user @tsialex had an insightful conversation with a user in a very similar predicament as me, almost identical!

“Some Chinese X5680 processors only work with uniprocessor boards, they are defective. Some sellers tell this, some not.”

So basically, one, or both of my x5680 CPU’s won’t work in pairs.

at least I have a few single core 5,1 machines that I can upgrade and search for two more CPU’s, but I’ll go with x5675’s since they draw less power ;)

Thank you everyone for your time and help :)
 
ArchStudent said:
Since the CPU’s are de-lidded all that I used was the original CPU’s plastic spacers and tightening to just hand tight, no over tightening.
Click to expand...

This might be a stab in the dark but when I was prepping for this upgrade I saw that I didn't need to use the spacers so I didn't and had no issues whatsoever. Maybe give it a shot and remove those spacers.

Good luck!
 
mikeydeezy said:
This might be a stab in the dark but when I was prepping for this upgrade I saw that I didn't need to use the spacers so I didn't and had no issues whatsoever. Maybe give it a shot and remove those spacers.

Good luck!
Click to expand...

Great idea, and thanks for sharing :)

I thought of that and tried that as well. Still gave me the same results/issues.

From the sounds of it, one or more of the processors could be defective whereby the only defect is that it does not work in pairs.
 
I did not delid my processors or trim the fan connector when I did this and had a similar experience.

Ultimately my problem was the CPU B heatsink wasn’t tight enough. First it wouldn’t boot. Tightened 1/16 a turn. Booted but missing ram. Tightened 1/16 a turn. Found the ram.

with de-lidded CPUs you shouldn’t have to worry too much about over tightening them. I believe the original Apple service manual just listed a torque spec, but I can’t recall what it was.

Good luck
 
ArchStudent said:
I may purchase x5675 CPU’s since they are nearly identical in power consumption to the original CPU’s. That is the only thing I can think of.
Click to expand...

I bought a pair of x5675 and have the same problem.
I bought two more - the same result.
But in one soccet - processors work perfectly.
 
Macschrauber said:
Have you swapped Ram Sticks around?
Click to expand...
Q 4 me? Yes. I have 6 stick about 8 gig each. No deal.
Try with ONE stick
When I swap delided cpu (yes - one pair of 5675 was delided) - red LED lit on B or A socket.
When I put into motherboard second pair of 5675 (not delided) - same issue. No boot.

Back to E5520 - boos normally.
 
Last edited:
Those 5675 are for 1333 Ram. They clock down with slower Ram. What happens if you put a 1066 Stick in?

I vote for a problematic / defective cpu board. But worth a test run with slower ram.

You can also try registered / unregistered Ram. But dont mix.
 
@minifridge1138 your insight about tightening an extra 1/16th of a turn is interesting. I picked up a dual processor 4,1 with a couple of bent pins as a bit of an experiment. Pins unbent, and it posts but get a KP (kmem_suballoc failed) as soon as it tries to load the install USB. I’ll try tightening the heatsink a tad to see if that helps.
Strangely apple hardware test says it only has 1 CPU and zero cores.
 
Macschrauber said:
Those 5675 are for 1333 Ram. They clock down with slower Ram. What happens if you put a 1066 Stick in?
Click to expand...
No deal at 1066. wont start

Macschrauber said:
I vote for a problematic / defective cpu board. But worth a test run with slower ram.
Click to expand...
? I dont think so. E5520 run normally.

Macschrauber said:
You can also try registered / unregistered Ram. But dont mix.
Click to expand...
Yes. All RAM = Registered.

Finaly - PSU is dead. (capasitor blow up) - I think enough is enough
Time to buy M1 ^)
 
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