Does Westmere support 8GB unbuffered modules?

[Chicken76]

I'm looking at this SuperMicro server motherboard (X8STi) and it says it supports up to 24GB DDR3 unbuffered memory. Having 6 slots, this means you can only use 4 GB modules.

Is this a limitation of the CPU, motherboard or BIOS? Or, were the 4GB modules the biggest unbuffered DIMMs available at the time this motherboard was on the drawing board?

 

[JoeRambo]

It is based on X58 and people (including me) successfully ran up to 48GB (6x8) on 920+ gen stuff, so I'd think you should have even less problems with Westmere gen CPU.

But of course it's impossible to know without testing, being server MB it might have crazy memory "initialization/validation" on startup.

 

[Stuka87]

I happen to have a bunch of those boards in servers. They are picky about their ram. I think SuperMicro released a BIOS update that supported 8GB DIMMs. But I do not have any 8GB DIMMs installed. I am also running fully buffered DIMMs, one of the main advantages to running a server board is for buffered DIMM support.

EDIT: Oops, they are X8DTL-6F's. Which is the dual socket version.

 

[zir_blazer]

I am also running fully buffered DIMMs, one of the main advantages to running a server board is for buffered DIMM support.

You're running Buffered/Registered. Fully Buffered were FBDIMMs and only existed as a DDR2 variant, which required their own, incompatible slot.


I recall some people that had issues trying to run 8 GB Unbuffered modules with Westmere-based Clarkdales, somehow they either didn't booted, or were unstable. Since the Memory Controller is part of the Processor, your Processor matters. Maybe Gulftown did better.

 

[Chicken76]

So it's safer to stick to 4 GB modules. Thanks guys.

 

[Emulex]

RDIMM also support both Data and Address line error correction/detection! Unbuffered dimms only protect the data lines IIRC.

 

[dave_the_nerd]

Crucial doesn't claim compatibility for anything larger than 4GB.

http://www.crucial.com/usa/en/compat...permicro/x8sti

Generally speaking, I'd trust 'em on this sort of thing - if they could sell you higher-priced parts, they would, after all.

For SuperMicro, I'd avoid buying from somebody without a return policy - their boards have a reputation for being... finicky.