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CodeJingle

macrumors 6502a
Original poster
Oct 23, 2009
592
217
Greater Seattle, WA
do they not get hot then?

heatsink_screenshot.png


http://downloadcenter.samsung.com/c...11307031/SAMSUNG_Memory_NVMe_Brochure_web.pdf
 
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CodeJingle

macrumors 6502a
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Oct 23, 2009
592
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Greater Seattle, WA
The iMac Pro is a single board CPU + GPU, so my idea to buy the iMac Pro GPU separately and put into a Mac Pro 2013 is not applicable. The fallback is again the Windows PC version of the Vega 64 board which is about $800 per GPU (which might not work).

This also means the only way to hook up a separate internal GPU to the iMac Pro is by physically damaging the board, compared to the Mac Pro 2013 which may only require pinout of the two graphics flex connectors on the logic board to connect different internal GPU. Hopefully, it keeps my work on the Mac Pro 2013 relevant [that the iMac Pro has a GPU that cannot be upgraded internally].

https://www.ifixit.com/Teardown/iMac+Pro+Teardown/101807

W3mK5hwyK4cIPVqC.png
 

MarkJames68

macrumors 6502
Sep 24, 2017
394
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Amazing that the GPU is soldered to the board...and I thought it couldn’t get worse than the 2013 Mac Pro...and then it did.
 

CodeJingle

macrumors 6502a
Original poster
Oct 23, 2009
592
217
Greater Seattle, WA
Amazing that the GPU is soldered to the board
I was sure the iMac Pro would not be 100% modular so I am glad the CPU and RAM are upgradeable. Though it makes sense for the iMac Pro GPU to not be modular it is still disappointing because GPU technology continues changing rapidly in the industry. Thankfully the coming Mac Pro 2018+ should have overpowered cooling and graphics that can be upgraded with 3rd party solutions. I don't necessarily care if the graphics or PCIe connector is standard as long as they provide the pinout instead of requiring reverse engineering.

I would be quite sore about another Mac Pro with only one processor socket I prefer DP or QP. I would be really feeling a QP Mac Pro that lets me plug in 4 graphics cards and 8 NVMe drives.
 
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AidenShaw

macrumors P6
Feb 8, 2003
18,667
4,677
The Peninsula
I was sure the iMac Pro would not be 100% modular so I am glad the CPU and RAM are upgradeable.
Being socketed does not make them upgradeable.

Often the BIOS will have checks for devices - and if the RAM or CPU isn't white-listed by the BIOS the system won't boot.

This practice can be defended by saying that workstations are important tools, and the system should reject untested RAM and CPUs in the interest of stability.

Unfortunately, this can lead to a no-boot situation when you have RAM or CPUs that are better than the listed set.
 
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MarkJames68

macrumors 6502
Sep 24, 2017
394
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Being socketed does not make them upgradeable.

Often the BIOS will have checks for devices - and if the RAM or CPU isn't white-listed by the BIOS the system won't boot.

This practice can be defended by saying that workstations are important tools, and the system should reject untested RAM and CPUs in the interest of stability.

Unfortunately, this can lead to a no-boot situation when you have RAM or CPUs that are better than the listed set.
What annoys me is that any GPU issues - and Macs have had quite a few over the years - mean a logic board change now. Why not solder the CPU, RAM and SSD too and have a truly throwaway Mac?
 

CodeJingle

macrumors 6502a
Original poster
Oct 23, 2009
592
217
Greater Seattle, WA
Unfortunately, this can lead to a no-boot situation when you have RAM or CPUs that are better than the listed set.

Apple is using standard 288-pin DDR4 ECC RAM sticks with standard chips, which iFixit was able to upgrade using its own $2,000 RAM upgrade kit.​

https://forums.macrumors.com/threads/imac-pro-ifixit-teardown.2098782/

Not sure about the CPU. No one has tried to swap it. But so far it works for RAM. Someone buy an iMac Pro and try swapping the custom CPU for a vanilla variant and see if it works! Then revert and return it.
 
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MarkJames68

macrumors 6502
Sep 24, 2017
394
246
Apple is using standard 288-pin DDR4 ECC RAM sticks with standard chips, which iFixit was able to upgrade using its own $2,000 RAM upgrade kit.​

https://forums.macrumors.com/threads/imac-pro-ifixit-teardown.2098782/

Not sure about the CPU. No one has tried to swap it. But so far it works for RAM. Someone buy an iMac Pro and try swapping the custom CPU for a vanilla variant and see if it works! Then revert and return it.
If it’s vanilla the TDP might be too high and you would get nasty thermal throttling.
 
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CodeJingle

macrumors 6502a
Original poster
Oct 23, 2009
592
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Greater Seattle, WA
If it’s vanilla the TDP might be too high, and you would get nasty thermal throttling.
The TDP limit is a problem with all motherboards, not just the boards locked down by Apple. I agree someone needs to test the full matrix of processors for this E and v of Xeon and figure out what the TDP limit is. I believe the TDP limit for Mac Pro 2013 is 130 watts.
 

MarkJames68

macrumors 6502
Sep 24, 2017
394
246
The TDP limit is a problem with all motherboards, not just the boards locked down by Apple. I agree someone needs to test the full matrix of processors for this E and v of Xeon and figure out what the TDP limit is. I believe the TDP limit for Mac Pro 2013 is 130 watts.
Correct, and all CPUs except for one fall under that limit, and even that one is equaled by the 130W E5-2667 V2 in performance.

The problem with the iMac Pro is that Apple started off with lowering max TDP...nowhere to go...
 

adonis3k

macrumors 6502a
Apr 15, 2012
547
109
Finally :)
[doublepost=1513448411][/doublepost]Installing and cross my fingers
[doublepost=1513450341][/doublepost]I tried the adapter I bought from the webshop first, and got many strange error messages and hangup. Then i tried the adapter shipped by CodeJingle and that worked perfectly :)

Did you need any tape on the adapter? Im still waiting for my fracking heatsink to arrive!
 

jclmavg

macrumors regular
Aug 2, 2014
173
105
Did you need any tape on the adapter? Im still waiting for my fracking heatsink to arrive!
I've been running for weeks now without heatsink, works just fine. Was too lazy to install it. As for taping, yes you'll need to shield it so it doesn't touch the edge of the connector.
 
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CodeJingle

macrumors 6502a
Original poster
Oct 23, 2009
592
217
Greater Seattle, WA
Can I use electrical tape or does it have to be Kapton stuff?
It needs to be very thin, or the adapter won't fit in the socket. Electrical tape or duct tape will be too thick. I would say heat tape is the only type of tape that is both electrically insulating and thin enough for this task.

Alternately it was suggested to put a conformal coating on the adapter instead of heat tape. I would recommend a legit conformal coating rather than nail polish. Heat tape and conformal coating will be priced similarly.

heat tape
https://www.digikey.com/product-detail/en/3m-tc/1-2-5-5419/3M10207-ND/2649752

conformal coating (pick 'Shopping')
https://www.google.com/search?q=422B+conformal+coating

more info on different types of conformal coating
https://www.mgchemicals.com/products/conformal-coatings/
 
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adonis3k

macrumors 6502a
Apr 15, 2012
547
109
Awesome got it working with my PM961, initial boot took a few minutes then did a time machine restore but after rebooting it went back into recovery and SSD was not showing. Shut down then started it up and it came back into life!

Thanks for all the info guys!

Are there any enclosures you can use with the OEM SSD? or might just sell it
 

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MarkJames68

macrumors 6502
Sep 24, 2017
394
246
Awesome got it working with my PM961, initial boot took a few minutes then did a time machine restore but after rebooting it went back into recovery and SSD was not showing. Shut down then started it up and it came back into life!

Thanks for all the info guys!

Are there any enclosures you can use with the OEM SSD? or might just sell it
Nice numbers....OWC makes one for a USB connection which would really limit the throughput.
 

CodeJingle

macrumors 6502a
Original poster
Oct 23, 2009
592
217
Greater Seattle, WA
Are there any enclosures you can use with the OEM SSD?
OWC makes one for a USB connection which would really limit the throughput.
I own this one. Throughput is pretty good for USB 3.0. Certainly not Thunderbolt or NVMe speed, but still good for the price (100 USD). Make sure you use a USB 3.0 cable. The drive is backward compatible with USB 2.0 cable, but then your throughput will decrease by 90%.

https://eshop.macsales.com/item/OWC/MAU3ENPRPCI/

original apple 1 terabyte mac pro 2013 ssd in external enclosure
20180109_153043_preview.jpeg


max throughput of the external enclosure
slow_speed.png
 
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CodeJingle

macrumors 6502a
Original poster
Oct 23, 2009
592
217
Greater Seattle, WA
equaled by the 130W E5-2667 V2 in performance
Yes, having the E5-2697 v2, I acknowledge the E5-2667 v2 is probably the best overall processor for the Mac Pro 2013.

The problem with the iMac Pro is that Apple started off with lowering max TDP
I am guessing the 18 core and 14 core custom processors are slight tweaks of Xeon W-2195 and W-2175, which are both 140W. The only difference appears to be increased cache size. The 10 core and 8 core processor choices for iMac Pro are underclocked compared to stock Xeon W-2155 and W-2145, which are also both 140W. In fact, all of the stock Xeon W chips are 140W.

8 core stock
https://ark.intel.com/products/126707/Intel-Xeon--W-2145-Processor-11M-Cache-3_70-GHz

10 core stock
https://ark.intel.com/products/125042/Intel-Xeon--W-2155-Processor-13_75M-Cache-3_30-GHz

14 core stock
https://ark.intel.com/products/130046/Intel-Xeon-W-2175-Processor-19_25M-Cache-2_50-GHz

18 core stock
https://ark.intel.com/products/126793/Intel-Xeon--W-2195-Processor-24_75M-Cache-2_30-GHz

stock comparison
https://ark.intel.com/products/series/125035/Intel-Xeon-Processor-W-Family

custom comparison (also screenshot in case apple changes the specs)
https://www.apple.com/imac-pro/specs/
42F0A728-85CE-4C8A-9094-58A21BFB3E8E.jpeg

comparison matrix between stock intel and custom apple (including speed / turbo / cache)

## core | stock ----------- | custom ---------- | delta (stock -> custom)
08 core | 3.7 / 4.5 / 11.00 | 3.2 / 4.2 / 19.00 | -14% / -07% / +73%
10 core | 3.3 / 4.5 / 13.75 | 3.0 / 4.5 / 23.75 | -09% / +00% / +73%
14 core | 2.5 / 4.3 / 19.00 | 2.5 / 4.3 / 33.25 | +00% / +00% / +75%
18 core | 2.3 / 4.3 / 24.75 | 2.3 / 4.3 / 42.75 | +00% / +00% / +73%


My current hypothesis is Apple purposefully chose to underclock their custom 8 core and 10 core processors so they wouldn't have to drive the fans harder. Their optimal cooling setup keeps it quiet. They hope you don't mind the underclocking given the extra cache they threw in there. I am thinking the board will still drive the stock processors at the higher frequency for 140W it just requires the fans to spin up a little more. The custom apple 14 and 18 cores are not underclocked so they might also drive the fans harder than the 8 and 10 cores. They aren't out yet so it doesn't damage the first impression media coverage (my claim chowder).

It makes sense for everything except the 8 core which they could have kept the turbo at 4.5 GHz like they kept for the 10 core. They only arbitrarily throttled the turbo for one of the four custom processor selections, the base processor, maybe as a kind of marketing tactic to wow everyone with how quiet and not hot the iMac Pro gets (more claim chowder - only works if the demo units they were showing off were sporting the 8 core). It is possible Apple's claim that the fans always blow the same speed and don't need to throttle up is only true for the 8 core (and only half true for the 10 core). When the 10 core is in turbo mode might also require the fans to blow harder. I just checked and as of Jan 10, 2018 the only processor available is the base 8 core. The quiet and not hot media hype will continue until the 10 core is released later this month and the 14, 18 core next month.

I would be peeved if Apple uses marketing tactics to make the Mac Pro 2018+ appear better than it really is. Add extra cache sure but don't underclock the processor just to win marketing brownie points. Make the cooling legitimately good and quiet (or quiet enough) without requiring underclocking, and make it work good with any processor not just the base model. Design it so 3rd parties can easily manufacture their own GPU upgrades and leave plenty of cooling headroom for future GPUs that might run hotter than the current generation.

Just peanut gallery talk here. If the underclock is not hard-coded, perhaps Apple's custom 8 core and 10 core can have the underclock reverted through a micro-code or some other type of firmware update if they eventually improve the cooling capacity versus audible noise for the iMac Pro (or give in and let it be a little noisy). Perhaps it could be a dynamic system setting the user can change at any time whether or not to underclock. I am guessing they are still working on improving the cooling efficiency of max TDP ~140W ahead of the 14, 18 core launch.
 
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