MP 1,1-5,1 Upgrading RAM in 5.1 cMP

[Reclzz]

Hi all

I saw a thread once with RAM talk, couldn’t find it now though. (If anyone knows where the thread is, It’ll be greatly appreciated)

I’m needing to upgrade my Mac Pro 5.1 2012 2 socket model.

Currently running 4x4 GB sticks, but eyeing a kit with 8x 16GB 1333 MHz Registered ECC on Ebay. Will it work no matter manufacturer or?

Cheers

 

[tsialex]

Hi all

I saw a thread once with RAM talk, couldn’t find it now though. (If anyone knows where the thread is, It’ll be greatly appreciated)

Mac Pro RAM Compatibility List

Mac Pro RAM Compatibility List This thread has information on the specifications of RAM for the Mac Pro models to help you determine compatibility. This is a Wiki post so anyone with the appropriate permissions may edit it. Please help others in the community by adding compatible RAM and fixing...

forums.macrumors.com

I’m needing to upgrade my Mac Pro 5.1 2012 2 socket model.

Currently running 4x4 GB sticks, but eyeing a kit with 8x 16GB 1333 MHz Registered ECC on Ebay. Will it work no matter manufacturer or?

Cheers

Only if 2Rx4. Any other type of ranking is not an officially supported configuration and could not work or work with penalties.

 

[Reclzz]

Ty.

I found some HYNIX HMT42GR7MFR4C-H9 instead but couldn’t find them in the thread.

And the 1600 Samsung sticks are only marginally more expensive. Probably gonna go with the Samsung sticks, even though the Hynix is available in Germany and Samsung stocks is either US or UK :/

 

[Soba]

Ty.

I found some HYNIX HMT42GR7MFR4C-H9 instead but couldn’t find them in the thread.

And the 1600 Samsung sticks are only marginally more expensive. Probably gonna go with the Samsung sticks, even though the Hynix is available in Germany and Samsung stocks is either US or UK :/

I'm not sure about cost of shipping to Europe, but check out Data Memory Systems. They guarantee compatibility and on the one occasion I received a bad stick from them (for my 2018 Intel Mac mini), they replaced it very quickly.

Also, a suggestion: If 96GB is adequate for you, consider installing 6 DIMMs instead of 8. The 2012 uses DDR3 RAM and works best with multiples of 3. Six DIMMs will yield a (very modest) performance increase as compared to eight DIMMs. It's only a few percentage points difference in performance and is not noticeable in most cases, but it's there.

If your application needs 128GB of RAM, then go for 8 DIMMs.

 

[sfalatko]

I had a similar quest earlier this year and followed @tsialex's advice to search marketplaces like ebay for server pulls.

I had success getting 48GB (3x16GB of Samsung M393B2G70DB0-YK0 16GB PC3-12800 2Rx4 DDR3-1600 MHz ECC Server Memory) for $100 from ebay.

Do a search, check the sellers reputation and return policy. I just did a quick search that yielded Samsung M393B2G70DB0-YK0 16GB PC3-12800 2Rx4 DDR3-1600 MHz ECC Server Memory for about $34 per memory stick including shipping to US addresses with 30 day return policy. The seller has almost 4000 reviews and a 100% rating.

Good luck.

 

[Reclzz]

Hello all

Hope you all had a merry Christmas and all!

I just ordered a pack (8x 16 Gb) of M393B2G70DB0 from a company in GB.

Which should be here between the 31/12 and 20/01 priced at £180 ($242 USD / €213 Euro) which seems like a great price to me.

Now I’m just playing the “waiting game”.

Cheers all

EDIT: Just checked today, price has jumped from £180 to £216 since I ordered mine, lucky me.

 

[Reclzz]

All ram is working as it should, over the moon with joy!

 

[Fastsavage]

Work out how much RAM you need as running 96Gb (6x16Gb sticks) arguably is faster than 128Gb (8x16Gb sticks) as it will use triple channel speeds

 

[macaddress]

Work out how much RAM you need as running 96Gb (6x16Gb sticks) arguably is faster than 128Gb (8x16Gb sticks) as it will use triple channel speeds

Explain this Triple channel, because I accidentally bought the quad channel sticks at 128gb and it was 1333 but since it was 4x4 it brought it down to 800mhz, However, I have the correct 2x4 sticks in now but it feels far more sluggish. Poor Benchmark scores compared to the 4x4 even running at 800mhz. Firefox crashes much faster opening multiple tabs etc. I hate to say it but it felt more clean and stronger with the 4x4 running at 800mhz and this was before i even put the radeon vii in.

 

[Fastsavage]

Explain this Triple channel, because I accidentally bought the quad channel sticks at 128gb and it was 1333 but since it was 4x4 it brought it down to 800mhz, However, I have the correct 2x4 sticks in now but it feels far more sluggish. Poor Benchmark scores compared to the 4x4 even running at 800mhz.

Firstly I would do a deep NVRAM reset

Turn off your Mac.
Restart your Mac and hold down Command + Option/Alt + P + R at start-up and I need to let it cycle 4 times, it might take a minute or 2. Then let go and let it start up as usual.


Secondly:
The Mac Pro's chipset has a triple-channel DDR3 memory controller, which will get full bandwidth only if you have just three modules per processor (slots 1,2,3 and 5,6,7)
The controller will run in dual-channel mode if you use all four slots
Theoretically you will get faster speeds using triple channel

 

[arw]

The Mac Pro's chipset has a triple-channel DDR3 memory controller, which will get full bandwidth only if you have just three modules per processor (slots 1,2,3 and 4,5,6)

You surely meant 1,2,3 and 5,6,7 (leaving the respectively 4th slot free for each processor).
Anyhow, I‘m totally with you. For my usecase I happily sacrifice some RAM for optimum computing power.

 

[Fastsavage]

You surely meant 1,2,3 and 5,6,7 (leaving the respectively 4th slot free for each processor).

Yes edited my post

 

[KeesMacPro]

I accidentally bought the quad channel sticks at 128gb and it was 1333 but since it was 4x4 it brought it down to 800mhz,

The 4Rx4 modules either dont work or run at 800 MHZ .
There is a way though to configure even 32GB 4Rx4 modules with OpenCore.
BjarneDM explains how to get it working here:

Crazy idea. 32gb ram modules in a cMP. Anyone tried this?

While MacPro5,1 CPU tray was designed for DIMMs with 1,5V VDD power rail, the standard voltage for DDR3, the PC3L DIMMs are backwards compatible and can run at 1,35V or 1,5V. So, you can use PC3L DIMMs with a MacPro5,1. Usually PC3L DIMMs when running at 1.5V have power draw very similar of...

forums.macrumors.com

 

[Fastsavage]

Anyhow, I‘m totally with you. For my usecase I happily sacrifice some RAM for optimum computing power.

Yes - I tossed up about 96 or 128 but I think I'll go for 96 as I don't need 128 and then it will be cheaper too

 

[macaddress]

The 4Rx4 modules either dont work or run at 800 MHZ .
There is a way though to configure even 32GB 4Rx4 modules with OpenCore.
BjarneDM explains how to get it working here:

Crazy idea. 32gb ram modules in a cMP. Anyone tried this?

While MacPro5,1 CPU tray was designed for DIMMs with 1,5V VDD power rail, the standard voltage for DDR3, the PC3L DIMMs are backwards compatible and can run at 1,35V or 1,5V. So, you can use PC3L DIMMs with a MacPro5,1. Usually PC3L DIMMs when running at 1.5V have power draw very similar of...

forums.macrumors.com

Is there a way to confirm you’re running triple channel? With that confuguation. Also wouldn’t you need a 3x4 stick? Because I can run 2x4 and 4x4. So using the 4x4 to default to 3? @. 800mhz

 

[macaddress]

Is there a way to confirm you’re running triple channel? With that confuguation. Also wouldn’t you need a 3x4 stick? Because I can run 2x4 and 4x4. So using the 4x4 to default to 3? @. 800mhz

Also, does the same go for the 7,1 with 4 modules as well?

I guess I’m trying to understand why we have 4 slots per processor anyways? That being said the 7,1 being ddr4, only use 4 of the slots to get the quad channel? Being that you have ddr4 with 4x4 sticks?

 

[macaddress]

Yes edited my post

is 3/4 7/8 shared? so 1.2.4. - 5.6.8 appears to be the correct channel config according this schematic. Otherwise what other arbitrary config make up 123, 567? - Pic from Apple inc.

 

[Fastsavage]

Yes, memory slots 3&4 and 7&8 share the same channels so the common config is 1,2,3 and 5,6,7.

I have a feeling (but I'm not sure) that you can't miss a slot out so you can't do 1,2,4 and 5,6,8

Maybe someone with more knowledge can fill in that blank...

 

[macaddress]

Yes, memory slots 3&4 and 7&8 share the same channels so the common config is 1,2,3 and 5,6,7.

I have a feeling (but I'm not sure) that you can't miss a slot out so you can't do 1,2,4 and 5,6,8

Maybe someone with more knowledge can fill in that blank...

This sounds confusing I was mixed up on the naming and rank. If there is a triple channel where is the 3rx4 pcbs available? The quad I bought was ranked 4rx4 ddr3 1333. Now I have the dual 2rx4 PCbs in. If that were the case. Then theoretically the 4Rx4 channel would have a much better chance getting a triple channel than the dual ranked pcb? Instead, supposedly 4rx4 just downgraded from 1333 to 800mhz. So no idea if was in quad dual or single channel mode, but was 4 ranked. And to make things even more convoluted I thought the chipset decided what the frequency was, x5690 should put out out 1333 and some chips 1066, or 800 in this case 4RxR did 800 with x5690 chipset why? No idea

 

[tsialex]

This sounds confusing I was mixed up on the naming and rank. If there is a triple channel where is the 3rx4 pcbs available?

Triple channel is running 3 DIMMs at the same time. While 3Rx4 DIMMs exists, it's not for MacPros.

The quad I bought was ranked 4rx4 ddr3 1333. Now I have the dual 2rx4 PCbs in. If that were the case. He 4Rx4 channel would had a much better chance getting a triple channel that the dual ranked pcb?

Quad rank is not even an officially supported type of DIMM to Nehalem and Westmere Xeons and have penalties when used, like downgrading from 1333MHz to 1066MHz/800MHz or not even being recognized.

MacPro5,1 was designed to work with dual rank DIMMs (2Rx4).

Edit: typo

 

[macaddress]

Triple channel is running 3 DIMMs at the same time. While 3Rx4 DIMMs exists, it's not for MacPros.

Quad rank is not even an officially supported type of DIMM to Nehalem and Westmere Xeons and have penalties when used, like downgrading from 1333MHz to 1066MHz/800MHz or not even being recognized.

MacPro5,1 was designed to work with dual rank DIMMs (2Rx4).

Edit: typo

So maybe I’m getting hung up on quad ranked and quad channel? I’m still lost on 3 dimms being triple channel where as 4 wouldn’t be quad? Dual ranked dimms run triple channel? The math or the labeling is not adding up

 

[tsialex]

So maybe I’m getting hung up on quad ranked and quad channel? I’m still lost on 3 dimms being triple channel where as 4 wouldn’t be quad? Dual ranked dimms run triple channel? The math or the labeling is not adding up

Ranking have nothing to do with channel in the way you think. 2Rx4/3Rx4/4Rx4 have nothing to do with the number of memory controller channels.

It's the memory controller design the defines the number of channels available, not the DIMMs. Channel is related to the width of the memory controller bus. Nehalem and Westmere Xeons used on a Mac Pro (Bloomfield and Gainestown), socket LGA1366, have a 216 bits bus (3x72bit).

There are Westmere Xeons for multiprocessor boards with quad channel (Beckton), but it's socket LGA1567. No Mac ever used one.

Slots 3 and 4 ( also 7 and 8 with dual processor CPU trays) share the same channel with a Mac Pro. Installing a DIMM on slot 4 elevates the load on the MemoryController and memory timings are then relaxed, that's why using 1 DIMM per channel have a better performance than using one DIMM per channel with channels 1 & 2 and two DIMMs with channel 3.

Again, slots 3 and 4 are the same memory channel.

 

[macaddress]

Ranking have nothing to do with channel in the way you think. 2Rx4/3Rx4/4Rx4 have nothing to do with the number of memory controller channels.

It's the memory controller design the defines the number of channels available, not the DIMMs. Channel is related to the width of the memory controller bus. Nehalem and Westmere Xeons used on a Mac Pro (Bloomfield and Gainestown), socket LGA1366, have a 216 bits bus (3x72bit).

There are Westmere Xeons for multiprocessor boards with quad channel (Beckton), but it's socket LGA1567. No Mac ever used one.

Slots 3 and 4 ( also 7 and 8 with dual processor CPU trays) share the same channel with a Mac Pro. Installing a DIMM on slot 4 elevates the load on the MemoryController and memory timings are then relaxed, that's why using 1 DIMM per channel have a better performance than using one DIMM per channel with channels 1 & 2 and two DIMMs with channel 3.

Again, slots 3 and 4 are the same memory channel.

Makes sense I was trying to understand the correlation

 

[macaddress]

Makes sense I was trying to understand the correlation

Good thing I asked, I did find it here in Minnesota but down by Mayo Clinic.
Was about to pick these up

Wasn’t there a thread where someone posted a spreadsheet here of many configs with 32gb ram ranging from 192gb and 256gb?

Also didn’t even know 32gb was an option. Any reason as to why our trays included the shared 4th dimm slot?

Edit: now I need to take a nap. Here it is again. What Mac uses this 3rx4??

 

[tsialex]

32GB DIMMs are not supported by macOS, you need OpenCore to make it supported and the config is complex/manual.

When MacPro4,1 was designed back in 2008ish, the usual DIMM was 1GB, with 2GB options, 4GB DIMMs were insanely expensive. Back then made sense to have a 4th slot sharing the 3rd channel to have more memory installed, even if it was slower.

3Rx4 is an unusual type of DIMM that started to be supported with some blade servers with IvyBridgeV2 Processors, no Mac ever used one.