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Objectivist-C

macrumors 6502
Jul 1, 2006
443
27
I bought a 2.5” Samsung 860 Evo that I was planning to run Boot Camp off of, but AHCI isn’t enabled for it and I’m getting half the rated speed. How can I enable it in Windows?
 

tsialex

Contributor
Jun 13, 2016
13,451
13,601
I bought a 2.5” Samsung 860 Evo that I was planning to run Boot Camp off of, but AHCI isn’t enabled for it and I’m getting half the rated speed. How can I enable it in Windows?
MP5,1 firmware defines SATA native ports as IDE and not as AHCI for Windows CSM mode. But this is not the motive of you getting half the expected throughput, it's because MP5,1 SATA ports are SATA 300.

Until we can find a way to edit CSM definitions inside the BootROM, you can't change it to AHCI for Windows installed as CSM.
 
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pacergh

macrumors newbie
Jun 4, 2010
4
0
I picked up a 5,1 Mac Pro at a University Surplus sale. Trying to diagnose non-boot issues. (I push the start button and get absolutely nothing.) Seems it is likely to be the PSU. Tried to test with the paper-clip test (found where someone else located the wired equivalent to ATX Green wires) and I was not apparently getting anything.

Which leads me to this -- Anyone tried to rewire an ATX PSU into Apple's proprietary PSU harness?

Alternatively, is there a good place to find PSUs?

Seems like PSUs may be the weak point in a lot of these in the future, and I was wondering if anyone had found the solutions yet.
 

h9826790

macrumors P6
Apr 3, 2014
16,656
8,587
Hong Kong
I picked up a 5,1 Mac Pro at a University Surplus sale. Trying to diagnose non-boot issues. (I push the start button and get absolutely nothing.) Seems it is likely to be the PSU. Tried to test with the paper-clip test (found where someone else located the wired equivalent to ATX Green wires) and I was not apparently getting anything.

Which leads me to this -- Anyone tried to rewire an ATX PSU into Apple's proprietary PSU harness?

Alternatively, is there a good place to find PSUs?

Seems like PSUs may be the weak point in a lot of these in the future, and I was wondering if anyone had found the solutions yet.

Jay did it, if you have facebook, you can check this out.

(Update, the video seems protected in a close group. Anyway, he did that.
Screenshot 2019-11-22 at 3.55.17 AM.png
 

pacergh

macrumors newbie
Jun 4, 2010
4
0
I think I found someone who traced the wiring. I did re-run the PSU test and it looks like it IS working. So, now I have to go down through the various things that could be wrong. Which may mean taking it all apart. Still might be the PSU (which is why I wish I could just plug in another), but need to run it all down. (Kind of fun; for $50 this is worth it. Lol.)
 

pacergh

macrumors newbie
Jun 4, 2010
4
0
Well, ran down the diagnostics. Looks like it is a Backplane issue or a processor/processor board issue. Going to look into it some more, see if it's worth maybe tinkering with and buying some parts, or if modding the case to fit a Hackintosh may be the way to go.

Are there good quality locations for spares for Mac Pro 5,1s? Or is it Ebay Roulette and other internet sources?
 

foonon

macrumors member
Aug 4, 2007
81
19
I upgraded my 2009 cMP to have a pair of 3.33 GHz 6-core Intel Xeon processors and 32GB Memory (4 8GB 1333 MHz DDR3s) last summer. In 2016 I installed an Nvidia GTX 680 2 GB graphics card.

Things have been going really well. I installed Mojave and its subsequent updates successfully (though I do get a prohibitory symbol when booting occasionally, easily overcome by manually selecting the boot drive by holding down the 'option' key when booting) and all the sound issues that were plaguing me went away after the CPU upgrade.

CPU temps and Fan speeds are usually nominal EXCEPT when doing any kind of video transcoding and today, the VTDecoderXPC and associated services send my fans into overdrive after I started the Photos application. BOOSTA & BOOSTB were spinning a 5200 RPM and the Exhaust and Intake fans were pinned at about 2800 RPM for several minutes. The CPU2 (Package Alt.) reading in "Temp Monitor" was not *that* high (70C), but it can get up to 90C when I'm running Handbrake.

Can anyone tell me what's going on and is there a way to fix it? Any help or pointers to help appreciated!

~f
 

Macschrauber

macrumors 68030
Dec 27, 2015
2,979
1,487
Germany
Check all temperatures, especially Northbridge. Inspect Northbridge rivets. You can see a bit of the 2nd when peeking with a flashlight under the heatsink
 

foonon

macrumors member
Aug 4, 2007
81
19
Check all temperatures, especially Northbridge. Inspect Northbridge rivets. You can see a bit of the 2nd when peeking with a flashlight under the heatsink

Northbridge temps are stable during light use (65C-75C). When the fans go into overdrive during video transcoding operations, the "Northbridge Die" temps actually plummet to ~40C.

~f
 

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Macschrauber

macrumors 68030
Dec 27, 2015
2,979
1,487
Germany
just fired up a Dual Mac Pro to double check.

CPU 2 Heat Sink to CPU 2 Die is a little high with 10 Degrees.

Fire up a stress test and monitor CPU 2 temps.

btw: Are those CPUs delidded ?
 
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foonon

macrumors member
Aug 4, 2007
81
19
just fired up a Dual Mac Pro to double check.

CPU 2 Heat Sink to CPU 2 Die is a little high with 10 Degrees.

Fire up a stress test and monitor CPU 2 temps.

btw: Are those CPUs delidded ?

They are delidded. CPU 2 has always run hotter, even before the upgrade.
 

mikas

macrumors 6502a
Sep 14, 2017
898
648
Finland
Aren't they called CPU A and CPU B normally (and by Apple too)?
What is the software used in above screenshots? It's calling those CPU 1 & 2, and all this is a little bit confusing now because of that. What do they correspond to? If A=1 and B=2 then the temperatures are the opposite from most other users experiences and measurements.

CPU A gets hot air from ram sticks installed in the front of it and from north bridge at the middle of the board, in front of CPU A, and it gets a little bit hot from CPU B too because of their placement in there (see pic). So the board installed in it's place inside the Mac Pro, CPU B is the one in front of the machine, and CPU A is at the rear side of the case.

Please see pics.
1586235153451.png

1586234794115.png
 
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foonon

macrumors member
Aug 4, 2007
81
19
Aren't they called CPU A and CPU B normally (and by Apple too)?
What is the software used in above screenshots? It's calling those CPU 1 & 2, and all this is a little bit confusing now because of that. What do they correspond to? If A=1 and B=2 then the temperatures are the opposite from most other users experiences and measurements.
...

It's a program called "Temp Monitor" from VIMI Studios.

A is 1 and B is 2, so A/1 is always going to be warmer under normal circumstances.
 

mikas

macrumors 6502a
Sep 14, 2017
898
648
Finland
According to user experience from this forum, A/1 would normally be the warmer one of the CPUs. The one near the rear of the machine.
 

foonon

macrumors member
Aug 4, 2007
81
19
I misread something Macschrauber said in post 187:

"CPU 2 Heat Sink to CPU 2 Die is a little high with 10 Degrees."

This lead to a mis-statement by me about CPU 2 being hotter than CPU 1.

I then (equally mindlessly) adjusted course after mikas' first reply. Obviously, I am in violent agreement with all points made there.

Apologies for any confusion this might have caused.

So now, I need to figure out why the difference between CPU 2/B Heat Sink and CPU 2/B Die temps is 10C. Perhaps I need to re-apply the thermal paste?
 

Macschrauber

macrumors 68030
Dec 27, 2015
2,979
1,487
Germany
no the difference is 6 to 12 degrees and it is normal

CPU A Differs less than CPU B, maybe a hint.

I get only a few degrees when the xeons are in lite use.

4 degrees on a single W3670 after 2 hours from diode to heatsink.

Check temperatures after a cold boot.
 

tsialex

Contributor
Jun 13, 2016
13,451
13,601
I misread something Macschrauber said in post 187:

"CPU 2 Heat Sink to CPU 2 Die is a little high with 10 Degrees."

This lead to a mis-statement by me about CPU 2 being hotter than CPU 1.

I then (equally mindlessly) adjusted course after mikas' first reply. Obviously, I am in violent agreement with all points made there.

Apologies for any confusion this might have caused.

So now, I need to figure out why the difference between CPU 2/B Heat Sink and CPU 2/B Die temps is 10C. Perhaps I need to re-apply the thermal paste?

CPU A heatsink gets the colder outside air while CPU B receives the warm air from CPU A. CPU B will never have the same temperatures as CPU A and the difference between the two usually grow as your ambient temperature is greater.

My idea about the motive of CPU B being warmer than CPU A was totally wrong, it's the reverse, CPU B gets the colder air from outside and still gets warmer, thx @mikas for pointing it out.


Anecdotally, My Dual CPU Mac Pro has a delta of ~6º in the winter months and sometimes over 10º in the peak of the summer.
 
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tommy chen

macrumors 6502a
Oct 1, 2018
907
390
CPU A Differs less than CPU B, maybe a hint.

I get only a few degrees when the xeons are in lite use.

4 degrees on a single W3670 after 2 hours from diode to heatsink.

Check temperatures after a cold boot.


dual X5690 + 6 x 16GB RAM

coldboot:

coldboot_0.jpg



after 30 min idle (manual fans!):

coldboot1.jpg



fan setting:

fans.jpg
 
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mikas

macrumors 6502a
Sep 14, 2017
898
648
Finland
CPU A heatsink gets the colder outside air while CPU B receives the warm air from CPU A. CPU B will never have the same temperatures as CPU A and the difference between the two usually grow as your ambient temperature is greater.
I think it's the opposite way (A versus B). Please see pics in post #190 .
 
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tsialex

Contributor
Jun 13, 2016
13,451
13,601
I think it's the opposite way (A versus B). Please see pics in post #190 .
You are right, had to open my dual CPU Mac Pro to confirm it. CPU B is the one nearer the front of the case, my idea of how CPU B is warmer was totally wrong.
 
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