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MP 7,1 Best RAM configuration for the 2019 Mac Pro
- Thread starter jasoncarle
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Oh my, I found that this diagram comes from Apple. It seems that the doc writers and the engineers (e.g. "About This Mac") have different ideas about "channels".
A single LGA 3647 Cascade Lake Xeon has two memory controllers with a total of six memory channels . Each channel can address two DIMMs . Thus , 12 ( 6 x 2 ) memory modules can be used in a MP7,1 . Easy Peasy !
Sooooo
I tried the 10 dimm config that you suggested, aaaaaand as opposed to what you'd expect, it actually worked!
I didnt try the 8 channels yet, but guess that would also work. Will try that out next.
What's interesting though is that with 10 dimms, my geekbench multicore score went down from 15600
to 14156.
So the non-6channel confic slows down the CPU quite significantly as it seems.
I guess I'll try 8 dimms and if the results are equally bad just gonna stick with 192gb for now and sell the 8gigs. Or someone tells me what new 8gig dimms to buy and I'll go to 12.
Well now I went ahead and tried 8 dimms as you recommended and it booted but gave me a warning that the configuration was not optimal. Then I followed the instructions given by the system and after that the orange light came back and it wollner boot at all ?
What is going on??
Is there a compatibility issue if some of the dimms are x4 and others are x8? Does the Mac Pro have a specific slot location if this occurs? Where can I find that information? Ideas?
Are you asking me, or the pros?
How to find out what the pre installed dimms even are?
I went back to 6 dimms: Geekbench Multiscore of 15960.
I think it's smarter to skip those 32gigs of ram for this performance gain!
I ordered two that are x8 and 4 that are x4 - didn't pay that much attention. I wonder if there is a specific location based on these specs...Are you asking me, or the pros?
How to find out what the pre installed dimms even are? View attachment 885829
Guess I'll wait for a pro to login!
Hi,
That 6x64GB you bought just went up to $1752.
I looked today as my Mac Pro just charged to my Apple Card.
Question.
what is the difference as the memory.net Samsung 1x64GB is PC4-23466U and Apple, OWC and Nemix list as PC4-23400?
Thanks
Paul
Apple lists the MP7,1 memory as DDR4 ECC at speeds of either 2666 or 2933 MHz .
The module names are thus either PC4-21333 or PC4-23466 .
That letter at the end of the name is a timing indicator . The lower the CAS latency , the better .
I have verified with my factory 8 Core MP7,1 that the standard factory 4 x 8GB ( 32 GB ) installation is actually 2933 MHz capable . With the 8 Core chip , it only goes as high as 2666 MHz .
No difference at all between 23466 and 23400. The former simply gives the bandwidth with more precision (of which your computer isn't capable), whereas the latter follows industry convention of dropping the last two digits.
It was $288/64GB when I bought mine - $292 now so not much of an increase. I used a code 'smile' to get another $50 off - you could see if that still works. The memory is working perfectly, no issues at all, and it's SO good to go from 32GB in my iMac to 384GB in the Mac Pro!
Yes, RAM prices are in a steady state of flux, meaning they are increasing as 3rd parties are obviously trying to cash-in on the demand many MP7,1 people are buying and shopping around and wanting to save money vs. paying the huge surcharge Apple is requiring for extra RAM.
For example, I purchased my 384GB RAM (12x 32GB R-DIMMs) for some $1,431 several weeks ago, and today this same amount of RAM from the same exact vendor is now charging $1,671 - a $240 increase.
For example, I purchased my 384GB RAM (12x 32GB R-DIMMs) for some $1,431 several weeks ago, and today this same amount of RAM from the same exact vendor is now charging $1,671 - a $240 increase.
I just bought my 384GB (6 of those 64GB Samsung LRDIMMs) from Memory.net too.
I also used smile for my coupon code to save 3%.
Spoke to a rep and got that $288 but had to go for the full 12.
Should get it by the time Apple ships my Mac Pro. Soooo excited!
Just confirming yes, ECC registered. I've been running it for 11 days now with no issues at all.
Just don't mix the x4 and x8 in the same channel. You should be fine then.
_great advice and i made sure not to...
the mac pro recognizes all the sticks and gives a green light on proper sequence. I thought so since they are all 32 gb chips.
I don:t think I will ever know the effect of having x4 and x8 ram.