Which RAM should I use?

[Zeke D]

Hey, everybody. I picked up some RAM from another member here on the boards, not realizing that I already had a 32GB kit. Not to worry, I can put one of the sets in the cMP4,1. So, which set is better for the cMP5,1?

And why do they show up as triple channel in the 4,1?

 

[tsialex]

I think that you are checking this the wrong way. You need to check the memory into the same Westmere processor.

With Nehalem and Westmere processors the controller is into the CPU, if you use a Nehalem processor, the memory controller works up to 1066MHz and Westmere ones up to 1333.

Btw, you need to zap-PRAM every time you change RAM into a Mac Pro to force the correct recognition of the modules into the NVRAM.