Does anyone know if it is possible to use 8x32GB DIMMs on a dual processor Mac Pro to get 256GB of RAM?
Got a tip for us?
Let us know
Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
MP 1,1-5,1 cMP & nMP {MacPro 4,1 & 5,1} Memory Upgrade Compatibility and FAQ
- Thread starter n8ballz
- WikiPost WikiPost
- Start date
- Sort by reaction score
- Status
[MOD NOTE]
Enough with the arguing. I've removed a number of posts as they were just going back and forth.
Enough with the arguing. I've removed a number of posts as they were just going back and forth.
There was a firmware update for High Sierra. Although I highly doubt that update would have changed the memory capacity of the Mac Pro, if anyone happens to have the RAM to spare for a test it might be worth checking.
This non ECC UDIMM can also be used in cMP. I actually used these DIMMs for few years.
ADATA AD3U1600W8G11-B
It is a 1600MHz DIMM. However, for this DIMM, if running 3x8GB, the RAM can run at 1333MHz without issue. But if install them in all 4 slots, the clock speed will be automatically reduced to 1066MHz. This DIMM also has life time warranty provided by ADATA.
![8GB UDIMM.JPG]( "8GB UDIMM.JPG")
ADATA AD3U1600W8G11-B
It is a 1600MHz DIMM. However, for this DIMM, if running 3x8GB, the RAM can run at 1333MHz without issue. But if install them in all 4 slots, the clock speed will be automatically reduced to 1066MHz. This DIMM also has life time warranty provided by ADATA.
I've been using 3 x 16GB Kingston 1333MHz RDIMMs (model KVR13R9D4/16) in my 6-core 5,1 for several years without issue.
One question I had was... would these modules work in a 2013 nMP 6,1 as well?
One question I had was... would these modules work in a 2013 nMP 6,1 as well?
Currently have three of those same 16GB RAM modules in a 5,1 6-core tray. They are 1333MHz DDR3 PC3-10600 ECC Registered CL9 240-Pin.
The 6,1 Mac Pro DIMMs are rated for 1866MHz DDR3 ECC. (Believe PC-14900.)
https://support.apple.com/en-us/HT202892
Believe the 32GB modules are capped at 1333MHz in the MacPro6,1. Know people who are using four of them (128GB total) currently in their 6,1 machines. Unsure if you'd "need" to add a 4th module, but they should work.
I believe the speed also depends on the CPU. 4 and 6 core are 1333 but lower speed for 8 and 12.
Speed depends on BOTH the CPU and the DIMM. The CPU usually has a RAM rating of two or three speeds, a DIMM rated at a speed faster than one the CPU will run at, will clock down. OTOH, a DIMM has one speed rating, but will clock down depending on the rating of the CPU.
Lou
Lou
This thread title and post are a bit mixed up. In the title, "cMP & nMP" would be 1,1 through 6,1. It then says "4,1 & 5,1" which are cMP only and not nMP. Then the actual post itself seems to be 5,1 only.
This thread is kind of what I'm struggling with right now. I want to run 48g, in 4x4 and 4x8 configuration in a 4.1 I have recently had intermittent problems with RAM slot 1 not reading, and have done a fair amount of troubleshooting, short of cleaning the contacts. Any suggestions would be appreciated. Heres what's reading now.
Last edited:
Hello there.
First time poster here in the UK with limited technical knowledge, just upgrading from a 2014 13" MBP i5 2.6Ghz.
I've just picked up a cMP 2010 QC 2.8Ghz with stock ITB SATA and a 5770.
I'm already adding a couple of SSD's, the PCIe usb 3.0 card is in and I'm waiting for the 6C 3.46G to arrive.
All I want to do now is use that last memory bay.
I already have x3 8GB Kingston 1333 *ECC* which, if I've done my research is running at 1066 due to my 4C processor.
My question is simply this; if I use non-ECC memory in the fourth bay will I see anything detrimental to what will be 32GB RAM?
Thanks.
First time poster here in the UK with limited technical knowledge, just upgrading from a 2014 13" MBP i5 2.6Ghz.
I've just picked up a cMP 2010 QC 2.8Ghz with stock ITB SATA and a 5770.
I'm already adding a couple of SSD's, the PCIe usb 3.0 card is in and I'm waiting for the 6C 3.46G to arrive.
All I want to do now is use that last memory bay.
I already have x3 8GB Kingston 1333 *ECC* which, if I've done my research is running at 1066 due to my 4C processor.
My question is simply this; if I use non-ECC memory in the fourth bay will I see anything detrimental to what will be 32GB RAM?
Thanks.
Last edited:
YES, all ECC will be disabled.
HOWEVER, you MUST make sure they are either ALL UDIMM or ALL RDIMM. You can't mix them together.
WRONG, I already proved that we can mix ECC with non ECC, different capacity, and different speed DIMM together.
https://forums.macrumors.com/threads/can-i-mix-memory-size.1903411/#post-21638766
Thanks for clarifying. I was always aware of capacity and speed, but not ECC. I still think putting non-ECC kind of defeats the purpose, especially with the cheap prices nowadays.
Thanks.
Will I see any loss of performance?
Yeah, I saw that in the sticky
I asked because I'm struggling a little to find ECC 8GB for a reasonable price in the UK
AFAIK, NO, in fact, may run up to 2% faster due to the error check is skipped.
actually i have mac pro 5.1 (4.1 flashed) Boot ROM Version MP51.0085.B00
i tried to add 2 x 32GB DDR3 4Rx4 to have 160GB ram,
but the mac pro don't like the 32GB sticks in any configuration.
slot 1 32GB
slot 5 32GB
mac pro don't start...no chime
slot 1 32GB
slot 2 16GB
slot 5 32GB
slot 6 16GB
mac pro start up with no problems, but it shows empty slots in slot 1 and 5 and total memory is only 32GB.
but somewhere mac pro see the 2 x 32GB sticks in slot 1 and 5 because
the total memory is downgraded from 1333mhz to 1066mhz speed.
usually i have 128GB ram running at 1333mhz.
if you have any idea why theses 32GB sticks
are not visible, thank you for your help and comments.
i resetted PRAM after intalling 32GB sticks,
thank you.
![photo 1.JPG]( "photo 1.JPG")
![photo 2.JPG]( "photo 2.JPG")
![photo 3.JPG]( "photo 3.JPG")
View attachment 762734
i tried to add 2 x 32GB DDR3 4Rx4 to have 160GB ram,
but the mac pro don't like the 32GB sticks in any configuration.
slot 1 32GB
slot 5 32GB
mac pro don't start...no chime
slot 1 32GB
slot 2 16GB
slot 5 32GB
slot 6 16GB
mac pro start up with no problems, but it shows empty slots in slot 1 and 5 and total memory is only 32GB.
but somewhere mac pro see the 2 x 32GB sticks in slot 1 and 5 because
the total memory is downgraded from 1333mhz to 1066mhz speed.
usually i have 128GB ram running at 1333mhz.
if you have any idea why theses 32GB sticks
are not visible, thank you for your help and comments.
i resetted PRAM after intalling 32GB sticks,
thank you.
Last edited:
The ram shown in the pic is a R4x4 32gb part. AFAIK... The 4,1/5,1 is compatible with R2x4 ddr3 RAM.
I’m currently running R2x4 16x16x16x8 with a 990x on a 4,1 flashed to 5,1
32 gigas Ram with one CPU ( Mac pro 4.1) not flashed = no trouble
Memory :
Samsung 8GB 2Rx4 PC3L-10600R-09-10-E1-D2 -> M393B1K70CH0-YH9
I'm hesitating on pulling the trigger on a RAM upgrade and this thread seems most likely to know the answer.
I literally just registered to ask my first (and probably last) question, so thanks to all in advance.
Also apologies in advance to any Moderators I may have annoyed if this is the wrong place to ask the question, but (see above) I almost certainly won't do it again
I have a single CPU 2010 cMP 5,1. Nothing like some of the monsters I'm seeing on here, but setup is (albeit in progress):
1 x CPU x5690, 1 x GPU Radeon RX580, 2 x PCIe 6GSSD and PCIe USB 3 Card. That's the basics anyway.
With a max upper limit of 64gb of 1333 ram in my configuration, can I use a 3 slot configuration of 1 x 32gb and 2 x 16gb
Is there actually a truly stable (if officially unsupported of course) 32GB module for a cMP 5,1.
As in a 32gb R2x4 ddr3 RAM, as mentioned above. I can't seem to easily search one at any rate.
FWIW my usage is 90% Logic Pro X (Home Studio, not pro), although for giggles I'm probably going to use it for a racing game or two. Think 'Need for Speed' here, not sim racing or the like. Also bear in mind that since the GPU supports it, I'm almost certainly going to try dabbling with a VR headset at some point soon as well.
I'm 48 and have ALWAYS maxed out RAM capabilities... we're talking since the mid-late 80's. Feel free to let me know whether or not that's still the necessary evil it used to be.
So for the first time in my life, I'm hoping for an answer along the lines of "Of course you can, you idiot newbie, didn't you read post blah blah blah, you goose!"
Hoping the answer helps other old fools like me reading this.
Thank you all again in advance.
I literally just registered to ask my first (and probably last) question, so thanks to all in advance.
Also apologies in advance to any Moderators I may have annoyed if this is the wrong place to ask the question, but (see above) I almost certainly won't do it again
I have a single CPU 2010 cMP 5,1. Nothing like some of the monsters I'm seeing on here, but setup is (albeit in progress):
1 x CPU x5690, 1 x GPU Radeon RX580, 2 x PCIe 6GSSD and PCIe USB 3 Card. That's the basics anyway.
With a max upper limit of 64gb of 1333 ram in my configuration, can I use a 3 slot configuration of 1 x 32gb and 2 x 16gb
Is there actually a truly stable (if officially unsupported of course) 32GB module for a cMP 5,1.
As in a 32gb R2x4 ddr3 RAM, as mentioned above. I can't seem to easily search one at any rate.
FWIW my usage is 90% Logic Pro X (Home Studio, not pro), although for giggles I'm probably going to use it for a racing game or two. Think 'Need for Speed' here, not sim racing or the like. Also bear in mind that since the GPU supports it, I'm almost certainly going to try dabbling with a VR headset at some point soon as well.
I'm 48 and have ALWAYS maxed out RAM capabilities... we're talking since the mid-late 80's. Feel free to let me know whether or not that's still the necessary evil it used to be.
So for the first time in my life, I'm hoping for an answer along the lines of "Of course you can, you idiot newbie, didn't you read post blah blah blah, you goose!"
Hoping the answer helps other old fools like me reading this.
Thank you all again in advance.
Last edited:
I believe you can do that, but why would you? (that's at least what I think I have read from threads here at MR)
That way you will lose triple channel bandwidth, versus with 3x16GB you get the ram cheaper AND get triple channel speed OR with 4x16GB you again lose triple channel, but the modules will be cheaper to buy versus 32GB+2x16GB.
If you own a 32GB stick already, then I understand the need for this.
I use 48GB in my single processor Mac Pros (4,1->5,1).
I once tried 56GB on a single proc (3x16GB+8GB), and I lost quite an amount of speed. So I took it back to 48GB.
(see attached pics, the same config exactly but the memory).
That way you will lose triple channel bandwidth, versus with 3x16GB you get the ram cheaper AND get triple channel speed OR with 4x16GB you again lose triple channel, but the modules will be cheaper to buy versus 32GB+2x16GB.
If you own a 32GB stick already, then I understand the need for this.
I use 48GB in my single processor Mac Pros (4,1->5,1).
I once tried 56GB on a single proc (3x16GB+8GB), and I lost quite an amount of speed. So I took it back to 48GB.
(see attached pics, the same config exactly but the memory).
Attachments
I'm hesitating on pulling the trigger on a RAM upgrade and this thread seems most likely to know the answer.
I literally just registered to ask my first (and probably last) question, so thanks to all in advance.
Also apologies in advance to any Moderators I may have annoyed if this is the wrong place to ask the question, but (see above) I almost certainly won't do it again
I have a single CPU 2010 cMP 5,1. Nothing like some of the monsters I'm seeing on here, but setup is (albeit in progress):
1 x CPU x5690, 1 x GPU Radeon RX580, 2 x PCIe 6GSSD and PCIe USB 3 Card. That's the basics anyway.
With a max upper limit of 64gb of 1333 ram in my configuration, can I use a 3 slot configuration of 1 x 32gb and 2 x 16gb
Is there actually a truly stable (if officially unsupported of course) 32GB module for a cMP 5,1.
As in a 32gb R2x4 ddr3 RAM, as mentioned above. I can't seem to easily search one at any rate.
FWIW my usage is 90% Logic Pro X (Home Studio, not pro), although for giggles I'm probably going to use it for a racing game or two. Think 'Need for Speed' here, not sim racing or the like. Also bear in mind that since the GPU supports it, I'm almost certainly going to try dabbling with a VR headset at some point soon as well.
I'm 48 and have ALWAYS maxed out RAM capabilities... we're talking since the mid-late 80's. Feel free to let me know whether or not that's still the necessary evil it used to be.
So for the first time in my life, I'm hoping for an answer along the lines of "Of course you can, you idiot newbie, didn't you read post blah blah blah, you goose!"
Hoping the answer helps other old fools like me reading this.
Thank you all again in advance.
Some thoughts...
The x5690 is limited to 64GB with a single CPU.
A single CPU x5690, when paired with 2R4 RDIMMS should give you 64GB without slowdown: I'm running a 990x, the consumer version of the x5690 without ECC support, with 56GB @ 16x16x16x8 and have posted Geekbench 4 results showing 4 sticks is faster.
A Raid 0 ramdisk delivers 2x the 4k performance of today's best NVMe SSD's, elevating any workflow. Working without a SWAP/VM file also helps.
16GB Samsung 2r4 ECC RDIMMS can be found on ebay for $40/GB on a good day. Usually $50 each. RDIMMS cannot be mixed with non-RDIMMS.
So yes.... Of course you can. The Mac pro upgrade matrix is not a single path.
Last edited:
Thank you MIKAS, but this isn't what I'm suggesting/considering (unless I'm completely confused)
In short, single cpu @ x5690 allows 64gb ram max @ 1333mhz
General consensus seems to be 3 slot over 4 slot.
So I figure 32gb (Slot 1) + 16gb (Slot 2) + 16GB (Slot 3) = 64GB utilising the 3 slot architecture for speed.
I'm just not sure if there is a 32gb module that will work in this configuration.
[doublepost=1531266917][/doublepost]
Thank you Handheldgames, I'm actually using the RAM 0 method on the PCIe SSD's.
So what you're saying is 32gb (Slot 1) + 16gb (Slot 2) + 16GB (Slot 3) = 64GB would be no faster than 4 x 16GB?
Last edited: