Supermicro CSE-826/X9DRi-LN4F+ Upgrades

[ryanm]

I am running a Supermicro X9DRi-LN4F+ (rev 1.20 w/ Bios v3.3) in a Supermicro 2U CSE-826A-R1200LPB.
2x Intel Xeon E5-2620 v1 HEx (6) Core @ 2.0GHz
32GB Hynix ECC Registered PC3-10600 (8 x 4GB) (5 x HMT151R7BFR4C-H9 and 3 x HMT151R7TFR4C-H9)

I am looking to upgrade the memory in this machine.

While shopping on eBay I see a lot of the ads referring to 1R, 2R, 4R. I know this refers to ranks. What I don't understand is if I can mix these. The motherboard has 24 memory slots, of which 8 are filled. What is my best option to bump this machine to 64GB or 96GB?

Will I get better value with another 8x4GB, which will still leave me with 8 slots to expand in the future? Or should I look at going for 4x8GB?
How does this affect dual/quad channel performance? Is it better to fill 12 slots or do I really need to expand in increments of 8?

Thanks!

 

[Sean Ho]

Yes you can mix ranks on this gen; you usually put the higher-rank DIMMs in earlier slots within each channel. Each channel is limited to a max of 8 ranks, so e.g., you cannot fill all 3 slots in a channel with quad-rank RDIMMs. Generally, denser is better. Beyond dual-channel, speed/latency improvements are marginal. If using LRDIMMs, logical ranks count against the 8R/channel limit. (LRDIMMs cannot be mixed with RDIMMs.)

 

[MBastian]

Have a look in the manual page 2-12, 2-14 and 2-15.
If you want 96GB I'd advise you to get 8x 8GB Modules PC3-10600 or better. Populating all three slots per channel would give you a memory performance hit.
Imho LRDIMMS are not worth their price if you are not hell-bent on having more than 256GB @ 1600 MT/s