SuperMicro X9DRG-QF max RAM at full speed?


[H]F Junkie
Aug 16, 2004
I just got a retired system with a SuperMicro X9DRG-QF motherboard. The case is also a SuperMicro case and has dual 1KW 80+ Platinum PSUs.

I plan on sticking 4x Quadro cards in this and using it primarily to mess around with GP-GPU programming.

Already ordered a couple 2697 v2 CPUs for it and want to eventually (soon) max out the RAM.

Looking at the old charts in the manual, it looks like the max at 1866 might be 256GB?

Anybody know if this is the case or can I go 512GB at 1866?
If you use LRDIMMs, you can usually run them at full speed if the cpu and chipset supports it. The e5 v1/v2 processors though had some strange LRDIMM support though as someone found out when trying to duplicate my 256GB setup in my hp z420.

Researching this particular motherboard, if you want 1866, you'll need to use LRDIMMs as regular 32GB RDIMMs will slow down as the ranks build up. The question is if your cpu will support LRDIMMs. In my hp z420, I have an e5-2630L and 8x 32GB LRDIMMs for a total of 256GB. (Well beyond the original HP specs of ECC UDIMMs only 32GB max.) Someone trying to duplicate my setup used the exact same memory modules but was using a v2 e5 and it wouldn't boot--turns out that LRDIMM support was removed from his v2 processor, which for the life of me I can't remember the model number or which forum we were discussing this on.

The alternate is that you should be able to get to 512GB using just 32GB RDIMMs, but they will slow down at least two speed levels, so 1066 I believe would be the fastest they would run, if not 800Mhz.

Hope this helps!