PowerEdge T310 - mixing different memories of different size

Hi Tomas.  Yes, you can Mix different sizes as such, as long each channel is balanced.  The T310 has two channels ( A & B). If you have 4 DIMMs currently, are they actually in A1, A2 and B2, B4? If so, you can add the 8 GB DIMMs (1 in each channel.) I recommend the larger DIMMs in the slots A1 and B2 (farthest from proc).  

Can you clarify that you are using both channels as described?

Hi,

thanks for your reply.

Hmmm, this is strange. iDRAC reports that there is 6 slots labeled as A1-A6. As I wrote the memories are in A1-A4. There are two free slots (A5 and A6) - all according to iDRAC. I can check it physically if you want. All memories were placed in the factory, we didn't changed it.

Best regards,

Tomas

No worries, i believe that is just a OMSA reporting issue. I've seen that on some other T310's in the past now that reflect back.  When you get a chance, open it physically to confirm that you see the white slots that represent the primary slots for each of the two channels.  I'll work on getting you some part numbers as reference as soon as i can.  I'm not finding it at the moment. 

Hi Bo,

you were right! OMSA (sorry, no iDRAC) reading is wrong, see attached picture. Slots are marked in the very same way as in your picture above. Slots 1-4 are used (A1, B1, A2, B2). Free slots are A3 and B3.

We have that memories now (the original ones from Dell's factory):

Hynix HMT351R7CFR8A-H9 (which is labeled as 4GB 2Rx8 PC3L-10600R-9-11-B1)

Would you think that for example following may be ok?

KVR13LR9S4L/8 (description is DDR3L, 1333MHz, ECC, CL9, 1R, X4, 1.35V, Registered, VLP)?

Then the configuraion would be:

A1, B1: 8GB

A2-A3, A2-A3: 4GB

Thanks and best regards,

Tomas

Hi Tomas,

Thanks for verifying the layout.  Just to clarify the slot should be A1, B2, A3, B4. Empty slots should be A5 and B6. (the odd numbers are on the A channel and the even numbers on the B channel). But nonetheless, yes, the 2 larger DIMMs will go in the white slots of A1 and B2. 

I can't say that KVR13LR9S4L/8 will work as it I'm not as familiar with VLP form factor for use in this server. I would rather you play it safe and go with an pair of 8GB DIMMs from the same type as what you have.  You can definitely use a brand other than Hynix though and you can mix single and dual ranks.

Hi Bo,

thanks for your information. I have all the information I need now. I will keep in touch with our local sales man.

After the upgrade I will post the results here and mark that answer as verified.

Thanks,

Tomas

Sounds great Tomas!

So, this one doesn't work (either two modules alone or with combination with current 4G memories):

Kingston memory 8GB 1066MHz Quad Rank Reg ECC x8 Module (KTD-PE310Q8/8G)

It seems that for 32 GB RAM in this server the only option is 4x 8GB Quad Rank memory (this seems to me like limitation of our CPU)

i have installed correctly 32gb 4x8gb , there is no way to install other 2 modules from 4gb each in the other 2 free ram slots?!

Hi,

The system supports up to 32GB of RAM using DDR3 registered RDIMMs