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Christian B. Mortensen

macrumors newbie
Original poster
Apr 27, 2020
1
0
Hey,

Just got a good deal on a 4.1 mac pro.
First thing I did was to flash it to 5.1

Question is, if I want to buy a dual cpu tray, which one should I get? a 4.1 model or a 5.1 model?
 

tsialex

Contributor
Jun 13, 2016
13,455
13,601
Everything you need to know about early-2009 and mid-2010/mid-2012 CPU trays is on this post:

 

Snow Tiger

macrumors 6502a
Dec 18, 2019
854
634
Surprise ! You actually need a factory Mac Pro 4,1 ( 2009 ) Dual CPU Tray . The Tray's SMC version must match the System's ( backplane ) SMC version or the fans go haywire , even if you have upgraded the model identifier .

You require both components to have a SMC version of 1.39f5 , in your case .

That's the good news .

The not so good news is the factory Mac Pro 4,1 ( 2009 ) Dual Processor Tray is harder to processor upgrade .
 

Teachermark01

macrumors member
Aug 22, 2020
39
0
you need a 4,1 CPU-tray!
a original 5,1 has a different SMC and your fans will allways blow at 100%
I've got this problem now... ? first upgraded everything to 5,1 and then change it. But is blowing like hell. Anything else I can do?
 

yurc

macrumors 6502a
Aug 12, 2016
835
1,014
inside your DSDT
I've got this problem now... ? first upgraded everything to 5,1 and then change it. But is blowing like hell. Anything else I can do?

How your CPU tray looks like? If you had a CPU tray with retention clips, I assumed you're using genuine 5,1 CPU tray, thus causing SMC version to miss match between backplane board and CPU tray, causing all fans set to full blast.

AFAIK SMC version cannot be changed by user, I am afraid you need to shell out real dual 4,1 CPU tray (indicates without retention clips on CPU socket). After everything done, you can sell your 5,1 tray.
 

flyproductions

macrumors 65816
Jan 17, 2014
1,086
461
I am afraid you need to shell out real dual 4,1 CPU tray (indicates without retention clips on CPU socket).
Might even be cheaper to look out for a cosmetically not so fine complete single CPU (real!!!) 5,1 with an intact mobo. Cases are very rare in which upgrading a single machine to dual CPUs makes any sense, economically.
 

flyproductions

macrumors 65816
Jan 17, 2014
1,086
461
I suppose you meant DUAL CPU...
No. Shouldn’t the 5,1 dual CPU-tray he has run nicely on some 5,1 single motherboard? So this could (at least here in Germany) be gotten for less than the 4,1 dual CPU-tray he needs to upgrade the machine he has.

Positive side-effect: The result would be a real 5,1 instead of some flashed wannabe.
 

KeesMacPro

macrumors 65816
Nov 7, 2019
1,453
596
No. Shouldn’t the 5,1 dual CPU-tray he has run nicely on some 5,1 single motherboard? So this could (at least here in Germany) be gotten for less than the 4,1 dual CPU-tray he needs to upgrade the machine he has.

Positive side-effect: The result would be a real 5,1 instead of some flashed wannabe.

Ah, I understand;)

About "a real 5,1 instead of some flashed wannabe" : since they are technically identical, I guess that depends on the importance of the cosmetic part to the owner...
 
Last edited:

minifridge1138

macrumors 65816
Jun 26, 2010
1,175
197
Ah, I understand;)

About "a real 5,1 instead of some flashed wannabe" : since they are technically identical, I guess that depends on the importance of the cosmetic part to the owner...
Not quite identical. The 4,1 uses lidless processors and is much trickier to do a cpu swap. On a 5,1 it’s normal processors. So if I was going through all the trouble of piecing together a machine, I’d go for the 5,1.
 
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KeesMacPro

macrumors 65816
Nov 7, 2019
1,453
596
Not quite identical. The 4,1 uses lidless processors and is much trickier to do a cpu swap. On a 5,1 it’s normal processors. So if I was going through all the trouble of piecing together a machine, I’d go for the 5,1.

I agree with you :I've done a few and installing some lidded CPUs is like a birthday party compared to a delidded install.
It's obvious that it's way more sensitive and needs some technical skills.

Another point is that the OP @Teachermark01 started with a single CPU 4,1 .
I think the investment of a 5,1 dual tray and 5,1 backplane is more than double the value of the 4,1.
Whether this is worth it ,just to avoid the risk/trouble/challenge or whatever way we see it is up to him ...

Once the CPUs are correctly installed, the only difference that remains will be an SMC version number ...
Which I consider a cosmetic detail.

EDIT: perhaps selling the 4,1 + 5,1 dual tray = price for a DUAL 5,1...
 
Last edited:

minifridge1138

macrumors 65816
Jun 26, 2010
1,175
197
I agree that once the swap is done, there’s no difference to the user.

I haven’t looked at prices in a while, but it could definitely be cheaper to buy a complete dual 5,1 Mac Pro than a 4,1 dual tray. A lot of it depends on the local market.
 
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flyproductions

macrumors 65816
Jan 17, 2014
1,086
461
Another point is that the OP @Teachermark01 started with a single CPU 4,1 .
I think the investment of a 5,1 dual tray and 5,1 backplane is more than double the value of the 4,1.
My understanding was he already has the 5,1 tray as well as the 4,1 and is now looking for the best / least expensive way of getting things to work.
 

Teachermark01

macrumors member
Aug 22, 2020
39
0
you need a 4,1 CPU-tray!
a original 5,1 has a different SMC and your fans will allways blow at 100%


I've upgraded mine 2009 4,1 mac pro with an 2009 4,1 dual CPU tray and fans are still blowing 100%.
What can I do to solve this? I've installed one CPU now Xeon 3,46ghz and 16gb ddr3 1066mhz RAM.

I left the other socket empty to test one delided CPU. What can I do next? Please help!
 

minifridge1138

macrumors 65816
Jun 26, 2010
1,175
197
I've upgraded mine 2009 4,1 mac pro with an 2009 4,1 dual CPU tray and fans are still blowing 100%.
What can I do to solve this? I've installed one CPU now Xeon 3,46ghz and 16gb ddr3 1066mhz RAM.

I left the other socket empty to test one delided CPU. What can I do next? Please help!
With only 1 CPU installed in the tray, the fans run 100%. That’s by design and there is nothing to “fix” except to install the other processor.
 

Teachermark01

macrumors member
Aug 22, 2020
39
0
are both smc Versions 1.39f5?

If you left one CPU empty fans go panic anyway
So now I put two in, still the fans are blowing like hell and now it's not booting also..
[automerge]1600810009[/automerge]
are both smc Versions 1.39f5?

If you left one CPU empty fans go panic anyway
Where can I check? I know they're both 2009 (because I first ordered the 2010 model, the wrong one)
 

Macschrauber

macrumors 68030
Dec 27, 2015
2,981
1,487
Germany
Well, if you need to delid it must be a 4.1 Tray. No need to investigate further.

imo the best method for single use is the vice method plus attaching heat.
 
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