16GB Modules in 2009 Quad core

[linuxcooldude]

Is it possible to put 4 X 16GB modules for a total of 64GB? Thanks.
[doublepost=1485802286][/doublepost]Checking with OWC they said only 3 X 16GB Module configuration is possible.

 

[owbp]

Well, OWC is kind of famous here

Yes it is possible if you're using dual processor capable Xeon, and you can go "only" to 56GB if you're using single processor capable Xeon. So, let's say you have 3,33GHz 6 core CPU in your mac:
- if your CPU is W3680 then only 56GB (3x16 and 1x8)
- if your CPU is X5680 then you can go to 4x16GB


All is explained here: https://forums.macrumors.com/threads/mac-pro-cpu-compatibility-list.1954766/

 

[linuxcooldude]

Thanks, helps out a lot and a few configurations I was not aware about. OWC website says you can't mix 16GB with different size modules? Thats with the 56GB configuration 3 X 16GB & 1 X 8GB Modules.

 

[Surrat]

Remember on your mac pro you will get maximum performance by using only 3 memory modules. Using 4, or different size modules to get 56GB, will slow it down... not a lot, but its there.

3 x 16GB would give you max performance.

 

[h9826790]

Thanks, helps out a lot and a few configurations I was not aware about. OWC website says you can't mix 16GB with different size modules? Thats with the 56GB configuration 3 X 16GB & 1 X 8GB Modules.

The real limitation is that you can't mix RDIMM with UDIMM, size doesn't matter.
[doublepost=1485882006][/doublepost]

Remember on your mac pro you will get maximum performance by using only 3 memory modules. Using 4, or different size modules to get 56GB, will slow it down... not a lot, but its there.

3 x 16GB would give you max performance.

It's true if the memory usage is less than 48GB. Otherwise, not necessary correct.