Mac Pro 5,1 Ram Upgraded beyond OWC and Ramjet published limits?

[JayMo51]

Hey everyone,

I am new to the forum, and upgrading my Pro tower as a whole and apologize if this has been covered elsewhere, but I searched and couldnt find anything. I recently purchased an A1289 tower from a local place here in Los Angeles that sells towers they've upgraded to Westmere processors from what I imagine are slightly older towers. From what it seems like to me, they buy a bunch of old Pro and frankenstein them all into different setups to maximize some, while selling off the leftover weaker rigs for parts. I ended up further upgrading the processor, putting in SSD's, and just decided to max out the Ram since I am doing a lot of video editing and FCP eats it up quickly. Basically what the rig amounts to in the end (according to the System Info and Hardware Overview) is an "early 2009" Mac Pro 5,1 running a 3.46- 6 Core Intel Xeon. It has 4 memory slots each of which takes a 1333 MHz DDR3 ECC mocule and was previously running at 32GB total. After a bit of research I found I could upgrade to 48GB max running a matching set of 3 @ 16GB ea, which I ordered through OWC. Out of boredom today I decided to drop one of my leftover 8gb Samsung modules into the vacant 4th slot, which I planned on either not showing up at all after startup, or failing to startup at all. But low and behold, after firing up my system info is showing 56GB of Ram and the machine is turbo charged. When running my serial number through everymac.com it turns up that this was originally a 2009 dual processor, 8 core Nehalem system, so not sure what would have been left behind that allows this, or if that is even part of the explanation.

I am quick to admit that I am new to this and have been using a Macbook Pro for years and only recently began to plunk around with this tower for fun and because Ive always loved the Pro towers and their possibilities, so I am looking to you all to tell me why this worked, if it in fact didnt work and Im dumb, if Im doing something stupid and need to take out the 4th module before I fry something, or anything else you may have for me. Thanks for the help!

Jared

 

[TzunamiOSX]

W-Series supports 56 GB. If you have an X5690 inside, you can use 64 Gb of RAM.

https://forums.macrumors.com/threads/mac-pro-cpu-compatibility-list.1954766/

But I think with your setup, the RAM is running in single channel mode.

 

[orph]

i think at the time your mac came out aka 2009 (or even 2008 when it was being designed) 16GBram sticks where not sold (yes it's that old) so as they cant test to see if it works on fictional RAM and no one cares to update spec once a computer is out etc..

so yep i think 96GB is the max? on dual cpu macpros.

4 sticks of the same ram may be faster ie 16GBx4 but it might only be by 0.1% so if it works just leave it.

edit -
see the cpu topic
https://forums.macrumors.com/threads/mac-pro-cpu-compatibility-list.1954766/

Mac Pro 5,1 and 4,1
Xserve 3,1

• Maximum RAM:
  • 56GB in a single-processor Mac Pro using a single-processor-capable Xeon
  • 64GB in a single-processor Mac Pro using a dual-processor-capable Xeon
    
  • 160GB in a dual-processor Mac Pro
  • 48GB for a single-processor Xserve
    
  • 96GB in a dual-processor Xserve

 

[h9826790]

Thanks for the report. This exact same situation was reported by MVC few years ago. However, what we still don’t know now is if we can get 32GB DIMM working on the single processor model. If yes, with which processor? And up to how much memory?

The limit with the dual processor cMP is very strange at this moment. 5x32GB = 160GB.

If we can use 32GB DIMM on the single processor cMP. We may actually able to get something like 96GB with a single X5690.

 

[JayMo51]

Wow, thank you all so much. I knew this would be the place to get answers. Looks like I can actually keep going on this thing. It seems that cramming more into these things becomes somewhat addicting. It's running great where Ive got it now, but Im sure Ill get the itch to see just how far I can take it soon, so Ill be sure to report back with any results or questions. And thanks a ton for the link to the compatibility post. Sorry I wasnt able to find it earlier on my own. But thanks again! Im loving this big old beast more and more each day.

Jared

 

[h9826790]

Wow, thank you all so much. I knew this would be the place to get answers. Looks like I can actually keep going on this thing. It seems that cramming more into these things becomes somewhat addicting. It's running great where Ive got it now, but Im sure Ill get the itch to see just how far I can take it soon, so Ill be sure to report back with any results or questions. And thanks a ton for the link to the compatibility post. Sorry I wasnt able to find it earlier on my own. But thanks again! Im loving this big old beast more and more each day.

Jared

If you can get some 32GB DIMMs with full refund policy protected. I really wish you can test it and report back when you have time to do it. Million thanks in advance!

 

[bsbeamer]

Haven’t found a retailer who would let me try 32GB sticks without a restocking fee. At $300+ per module, more than I can afford to risk at the moment.