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markwilliams432

macrumors newbie
Original poster
Nov 5, 2014
21
27
Hi All,

Does anyone know if the RAM on the iMac Pro has a preparatory thermal sensor? I have fitted replaced the 32GB standard RAM and replaced it with 128GB of exactly the same specification RAM and the fan runs at full RPM. To check I didn't damage anything I replaced the 32GB RAM and the fan runs at normal RPM.

Anyone here also tried this? If not I guess I will keep having to try different RAM manufacturers.

Before you ask 'Why void warranty on such an expensive machine' I purchased this RAM for £700 ($850). Over £2000 from Apple seams very steep.
 

anticipate

macrumors 6502a
Dec 22, 2013
936
768
Hi All,

Does anyone know if the RAM on the iMac Pro has a preparatory thermal sensor? I have fitted replaced the 32GB standard RAM and replaced it with 128GB of exactly the same specification RAM and the fan runs at full RPM. To check I didn't damage anything I replaced the 32GB RAM and the fan runs at normal RPM.

Anyone here also tried this? If not I guess I will keep having to try different RAM manufacturers.

Before you ask 'Why void warranty on such an expensive machine' I purchased this RAM for £700 ($850). Over £2000 from Apple seams very steep.

I have not but I am very curious what your findings were. Is it a royal PITA to install?
 

markwilliams432

macrumors newbie
Original poster
Nov 5, 2014
21
27
I have not but I am very curious what your findings were. Is it a royal PITA to install?
It is very similar in regards to difficulty as the 27" 2017 iMac. Obviously there are hardware differences but its all very similar. The only tricky part is the removal of the main board, it really is stuck under the bottom of the chassis.
 
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Samuelsan2001

macrumors 604
Oct 24, 2013
7,729
2,153
Hi All,

Does anyone know if the RAM on the iMac Pro has a preparatory thermal sensor? I have fitted replaced the 32GB standard RAM and replaced it with 128GB of exactly the same specification RAM and the fan runs at full RPM. To check I didn't damage anything I replaced the 32GB RAM and the fan runs at normal RPM.

Anyone here also tried this? If not I guess I will keep having to try different RAM manufacturers.

Before you ask 'Why void warranty on such an expensive machine' I purchased this RAM for £700 ($850). Over £2000 from Apple seams very steep.

Well it may have to be set up by an apple tech for the fans to work correctly etc, you were warned it wasn't user upgradeable, now you know why.
 

markwilliams432

macrumors newbie
Original poster
Nov 5, 2014
21
27
Well it may have to be set up by an apple tech for the fans to work correctly etc, you were warned it wasn't user upgradeable, now you know why.
We were warned it wasn't user upgradable by Apple so the maintain a huge mark up. I have upgraded every Apple system I've ever owned. Paying 300% premium for CPU's, RAM or Storage is crazy!
 

joema2

macrumors 68000
Sep 3, 2013
1,646
866
...replaced it with 128GB of exactly the same specification RAM and the fan runs at full RPM. To check I didn't damage anything I replaced the 32GB RAM and the fan runs at normal RPM....

iFixit did a teardown of the iMac Pro and they are working on an upgrade guide but it's not published yet. https://www.ifixit.com/Teardown/iMac+Pro+Teardown/101807

Likewise OWC tore one down and they say they are also working on a RAM upgrade. I don't know if there's some trick to the RAM affecting the fan speed: https://blog.macsales.com/43267-owc-tears-down-the-2017-imac-pro-announces-future-upgrade-programs
 

Bryan Bowler

macrumors 601
Sep 27, 2008
4,067
4,442
I know you said you replaced it with RAM that’s the same specs, but I’ve never seen 128 GB of iMac Pro RAM for $850. As a matter of fact, I’ve never seen prices even remotely in that price range.

Where did you get the RAM? It seems to me that there’s a high likelihood that you got scammed.
 
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bxs

macrumors 65816
Oct 20, 2007
1,151
529
Seattle, WA
I know you said you replaced it with RAM that’s the same specs, but I’ve never seen 128 GB of iMac Pro RAM for $850. As a matter of fact, I’ve never seen prices even remotely in that price range.

Where did you get the RAM? It seems to me that there’s a high likelihood that you got scammed.
Yes, I'm of the same opinion on the price for 128GB RAM (presumably;y 4x 32GB modules). From my research the difference between buying 4x 32GB from 3rd party and the price Apple charges for the 128GB RAM is around $300-$400. That is 3rd party 4x 32GB RAM modules of the correct specifications for the iMac pro is around $2000. Add to this the effort and cost of disassembling the iMac Pro (and voiding warranty) makes buying the RAM you need from Apple when you order to be a reasonable expense.

Note to the OP..... What are the specs for the 128GB RAM your bought and where did you buy it from ?
 

joema2

macrumors 68000
Sep 3, 2013
1,646
866
Did the OP use EEC RAM?? That could well be the issue.

Also was it 2666Mhz registered DDR4? The iMac Pro requires that, which is expensive. E.g, this OWC RAM is about $1500 for 128GB: https://www.amazon.com/dp/B01N5HME0X/ref=cm_sw_r_cp_ep_dp_mm2vAbJ12PNB2

This 128GB ECC kit from Crucial is nearly $1700: http://www.crucial.com/usa/en/ct4k32g4rfd4266

I'm not sure if those are guaranteed to work in an iMac Pro, but that's more in the price range of what you should expect for compatible ECC DDR4 2666Mhz RAM.

The 2013 Mac Pro used DDR3 1333 Mhz RAM, which OWC sells for about $1100 for 128GB. I could see some super-deal on *that* being maybe $850, but it's not designed for the iMac Pro.

OWC has a complete 128GB iMac Pro RAM upgrade kit -- it is $2000: https://www.ifixit.com/Store/Mac/iMac-Pro-Memory-Maxxer-RAM-Upgrade-Kit/IF382-003-1

So Apple's pre-configured built-to-order RAM upgrade price of $2400 (high as it is) suddenly doesn't look so extreme. If you want it to work right, you have to use compatible RAM.

Hypothetically, if the above OWC RAM worked, and if an authorized 3rd-party local shop charged $200 for the labor (just a wild guess), you'd save about $700 over the Apple price -- on a machine that might cost $7000-$8000. That would be a useful savings. But if the Crucial RAM was required and the service cost to install it was $300, then the savings (over Apple pre-installed RAM) diminishes to $400.
 

haruhiko

macrumors 604
Sep 29, 2009
6,693
6,245
It seems that you have bought the wrong RAM. #Facepalm
The price difference of Apple’s RAM is there but not as much as you think.
 
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Samuelsan2001

macrumors 604
Oct 24, 2013
7,729
2,153
Also was it 2666Mhz registered DDR4? The iMac Pro requires that, which is expensive. E.g, this OWC RAM is about $1500 for 128GB: https://www.amazon.com/dp/B01N5HME0X/ref=cm_sw_r_cp_ep_dp_mm2vAbJ12PNB2

This 128GB ECC kit from Crucial is nearly $1700: http://www.crucial.com/usa/en/ct4k32g4rfd4266

I'm not sure if those are guaranteed to work in an iMac Pro, but that's more in the price range of what you should expect for compatible ECC DDR4 2666Mhz RAM.

The 2013 Mac Pro used DDR3 1333 Mhz RAM, which OWC sells for about $1100 for 128GB. I could see some super-deal on *that* being maybe $850, but it's not designed for the iMac Pro.

OWC has a complete 128GB iMac Pro RAM upgrade kit -- it is $2000: https://www.ifixit.com/Store/Mac/iMac-Pro-Memory-Maxxer-RAM-Upgrade-Kit/IF382-003-1

So Apple's pre-configured built-to-order RAM upgrade price of $2400 (high as it is) suddenly doesn't look so extreme. If you want it to work right, you have to use compatible RAM.

Hypothetically, if the above OWC RAM worked, and if an authorized 3rd-party local shop charged $200 for the labor (just a wild guess), you'd save about $700 over the Apple price -- on a machine that might cost $7000-$8000. That would be a useful savings. But if the Crucial RAM was required and the service cost to install it was $300, then the savings (over Apple pre-installed RAM) diminishes to $400.

Even saving $700 is not worth losing your warranty over especially when you are spending that much on a computer anyway.
 

markwilliams432

macrumors newbie
Original poster
Nov 5, 2014
21
27
I know you said you replaced it with RAM that’s the same specs, but I’ve never seen 128 GB of iMac Pro RAM for $850. As a matter of fact, I’ve never seen prices even remotely in that price range.

Where did you get the RAM? It seems to me that there’s a high likelihood that you got scammed.
The company I work for buy in 1000's of memory modules a year and have access to distributors.
[doublepost=1515747503][/doublepost]I guess the prices you are all quoting are retail and we aren't paying those prices. The RAM purchased in attempt 1 was

32GB 2Rx4 pc4 2666v bb2 11 db1 and manufactured by Samsung
 

maflynn

macrumors Haswell
May 3, 2009
73,682
43,740
32GB 2Rx4 pc4 2666v bb2 11 db1 and manufactured by Samsung
But is it EEC? Googling it seems to indicate that it is EEC

While Apple has a markup and I do beleive that markup is not huge compared to other memory for the iMac Pro, you are risking damage to a computer that is virtually sealed. I'm not trying to lecture you on what you ought or ought not do, but rather point out paying a small premium for someone else to do the work is not a bad thing especially when it comes to warranties, and not damaging the comptuer.

As for your situation, is it possible that you did not correctly plug in any sensor modules, or damaged something taking it apart (or putting it back together?)
 
Last edited:

joema2

macrumors 68000
Sep 3, 2013
1,646
866
The company I work for buy in 1000's of memory modules a year and have access to distributors.
[doublepost=1515747503][/doublepost]I guess the prices you are all quoting are retail and we aren't paying those prices. The RAM purchased in attempt 1 was

32GB 2Rx4 pc4 2666v bb2 11 db1 and manufactured by Samsung

I don't know why your fan is running at high speed. Here is a close-up photo of the iFixit 32GB RAM, maybe you can look up some numbers for this and compare it to your Samsung RAM:

https://photos.smugmug.com/photos/i-tw2Df4Z/0/cef3b490/O/i-tw2Df4Z.jpg
 
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