X10SRH-CF and maximum ECC RDIMM RAM?

[Scampicfx]

Dear guys,

when looking at the manual of X10SRH-CF (Link: https://www.supermicro.nl/products/motherboard/Xeon/C600/X10SRH-CF.cfm ), I notice that Supermicro describes up to 256GB ECC RDIMM as a maximum amount of RAM when using RDIMMs.

Well... When looking at the "Tested Memory List", I notice that there is a Samsung 64 GByte ECC RDIMM DDR4 2133 module listed:
https://www.supermicro.nl/support/resources/memory/display.cfm?sz=64.0&mspd=2.133&mtyp=68&id=A721EC1653DC4E463DC1C9D03BC5A7D2&prid=84053&type=DDR4 1.2V&ecc=1&reg=1&fbd=0

However, populating the mainboard with 8 of these ram modules would increase the maxium rdimm capacity to 512 GByte...

So my question is: Does anyone know what is the maximum possible amount of rdimms? Is it possible to place 8x 64 GByte ECC RDIMMs and thus use 512 GByte ECC RDIMMs?

 

[Ericloewe]

You might want to ask Supermicro and then tell us their answer. I can see it going both ways.

 

[Jailer]

I suspect that it depends on the type or rdimm in use. From Supermicro product description:

Memory Capacity

• 8x 288-pin DDR4 DIMM slots
• Up to 1TB ECC 3DS LRDIMM
• Up to 512GB ECC LRDIMM
• Up to 256GB ECC RDIMM

 

[TXAG26]

How about going with LRDIMM's? I think they may actually be less expensive than the 64gb RDIMM's at the moment.

My experience has been you go down a step in speed once you add more than 4 RDIMM's to these E5-26xx v3/v4 systems. It's my understanding that LRDIMM's allow 8 sticks in the system before dropping down a step in speed.

 

[Scampicfx]

Hey guys,

I had some emails with Supermicro... Here is the most relevant one:

Hi,

Per our engineer:
“
>> Q: According to MB manual, it only support up to 256GB RDIMM (8x32GB DIMM) or 512GB LRDIMM (8x64GB DIMM)
A: The differences between RDIMM and LRDIMM (Load reduce Registered DIMM) is: LRDIMM can handle more capacity and speed.
>> Q: Is it possible to populate 8x64 RDIMM to get 512 GB?
A: It might be yes but it need to do some test to verify if it working.

Assume end user have 4x64GB RDIMM

1. Populate 4 DIMM on 2 channel DIMMA1, DIMMA2, DIMMB1, DIMMB2. System should recognize 256GB DIMM or system report memory error. If system error, then memory load issue. If it working, then run some memory stress test.
2. Try above method with swapping memory to DIMMC1,C2,D1,D2 and run test again.

If both conditions work. End user can try with 8x64GBR DIMM“

So, there is no official statement regarding 64 G RDIMM modules... It might work, but it is not officially tested...

Therefore I recommend to stick to manual/website and use maximum 32 GByte RDIMMs, but not the 64 GByte RDIMMs... When 64 GByte DIMMs are necessary, I would also recommend to go with LRDIMMs - to be on the safe side...

Thanks for all your answers so far!