[SOLVED] Number of memory modules for Supermicro motherboards

[Leo_UAM]

Hello All,

I have a Supermicro H8DGi-F motherboard and two modules Samsung 32GB DDR3 4Rx4 PC3L-12800L ECC (at least the stickers say so).
When powering on the system, it gives 5 beeps like there is a memory problem. The board manuals says "Always install in groups of four and in the numerical order of the DIMM slots."
Does it mean that I actually have to use four modules for each channel?

 

[rgd1101]

it a dual cpu socket. what is your full system spec?

 

[kanewolf]

Hello All,

I have a Supermicro H8DGi-F motherboard and two modules Samsung 32GB DDR3 4Rx4 PC3L-12800L ECC (at least the stickers say so).
When powering on the system, it gives 5 beeps like there is a memory problem. The board manuals says "Always install in groups of four and in the numerical order of the DIMM slots."
Does it mean that I actually have to use four modules for each channel?

You are going to have to dig deeper into the part number of your memory.
The manual says up to 128 GB of ECC/Non-ECC UDIMM or 512 GB of ECC RDIMM
So you need to find out if your 32GB DIMM is unbuffered (UDIMM) or registered (RDIMM) it is probably an RDIMM at 32GB with DDR3.
The operon CPUs are quad memory channel CPUs. For optimum performance you WANT memory in multiples of four for a single CPU and eight for dual.

My guess is your 32GB DIMMs are not supported by that motherboard.
The Supermicro website has a list of tested DIMMs, is your memory on that list ?

 

[Leo_UAM]

I have two G34 Opteron 6172 CPUs. Yes, it is ECC registered.

No, it's not in the tested memory list.
The one tested is M393B4G70AM0-CF8 and mine is M386B4G70DM0-YK. I decided to try my luck, because I couldn't find the tested memory. I think the list of compatible memory is bigger than the one given on the Supermicro webpage.

If I had two modules of tested memory from the list, it would still give the beep, right? So the reason might be also due to the lack of missing 6 modules

 

[bignastyid]

What slots is the ram installed in? With 2 cpus you need ram for both so with single channel ram should be in P1-1A and P2-1A.
For optimal performance it does require groups of 4(quad channel)

With 1 cpu installed you'll need atleast 4 dimms in slots P1-1A, P1-2A, P1-3A, P1-4A.
With 2 cpus installed you'll need 8 dimms P1-1A, P1-2A, P1-3A, P1-4A, P2-1A, P2-2A, P2-3A, P2-4A.

 

[Leo_UAM]

I tried these modules in P1-1A and P2-1A. It didn't work either.