Mixing RAM densities in a Dell server?

We have a Dell PowerEdge gen 12 server that is capable of a total 384 GB of RAM and has 12 RAM slots total.  Currently, we have a total of 32 GB of RAM occupying 4 slots at 8 GB each.

I would like to upgrade this server at some point in the future using higher density RAM of the same specifications as RAM prices go down, making maximum use of the slots available.  But I would like to of course continue to be able to use the existing ones.

My question is, can I mix RAM density types if all other specs and brand are exactly the same?  My guess is yes, but just wanted to double check.  Also, I am guessing that they will need to be paired in some sort of slot staggered order?

Thanks.
CnicNVAsked:
Who is Participating?

Improve company productivity with a Business Account.Sign Up

x
 
andyalderConnect With a Mentor Commented:
Yes although there's no requirement to match the speed of the current ones, but if you put slower ones in then all the RAM will run at the slower speed.
0
 
Neil RussellTechnical Development LeadCommented:
Unlikely if it is a newer server.  Please specify exactly what server you have as they will specify exactly what memory configurations are available for that model based on what processor configuration you have.
0
 
Seth SimmonsSr. Systems AdministratorCommented:
sure, you can add 16gb modules if you wanted, but no more than 2 different sizes
for number of modules, depends if you have 1 or 2 processors
you can add a 16gb module if you have one processor but have to put 2 modules if you have 2 processors (1 in each channel)

if you have 2 processors, you can add 8 16gb modules giving you an additional 128gb
of course, how much of that you can use is dependent on the operating system
0
Easily Design & Build Your Next Website

Squarespace’s all-in-one platform gives you everything you need to express yourself creatively online, whether it is with a domain, website, or online store. Get started with your free trial today, and when ready, take 10% off your first purchase with offer code 'EXPERTS'.

 
andyalderCommented:
Just about every new Intel or AMD based server lets you mix capacities and even speeds and number of ranks, the only hard and fast rule is you can't mix RDIMMs with UDIMMs or LRDIMMs. Population rules vary slightly and it's a fraction faster having the same amount of RAM on each memory channel, you've probably got 3 or 4 channels per CPU. Try to ensure the same of amount of RAM on each CPU.

384GB suggests 12 * 32GB dual rank DIMMs max, if you confirm the machine you have someone will recommend what to put in which slot.
0
 
andyalderCommented:
Silly me, that would be 12 * 32GB quad rank at 2DPC, there aren't 32GB dual rank although 32GB load reduced DIMMs look like 2 ranks to the CPU.
0
 
CnicNVAuthor Commented:
Sorry for the delay, holidays/their lead up and all that.

This server is a 12th generation Dell Poweredge r420 with 4 8GB RDIMM chips at 1600mhz.  So I am gathering from most of the feedback that as longs as I buy RAM that is of a "Dell supported" brand in the 1600mhz RDIMM configuration, mixing any densities up to 32 GB should be fine?
0
 
CnicNVAuthor Commented:
Ok perfect.  Thanks for the help :)
0
Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

All Courses

From novice to tech pro — start learning today.