We have a Dell precision t7600 it has 32gb of ram in 8 blocks of 4 gigs
Samsung 4gb 2Rx8 PC3-128004-11-11-b1-p2
Part no: M393B5273DH0-CKO

We still have 8 slots available, and we want to buy another 32gb. Dell want silly silly money.

So the trouble is I cannot get exactly the same part no modules. I have found alternative samsung modules that are pc12800, but they are not exactly the same part no.

Any advice? Or anyone know good supplier of samsung memory?

have you tried turning it off and on again?

Use the system scanner on http://www.crucial.com/uk it’ll give you a list of compatible modules. Fairly cheap as well.

http://www.crucial.com/uk/systemscanner/

Check the max ram on dell diagnostic and buy 2×16 or 4×8 of whatever spec it is num of pins speed eec etc

Wow,

that’s really expensive RAM

http://www.crucial.com/uk/store/listparts.aspx?model=Precision%20Workstation%20T7600&Cat=RAM

Go to http://www.crucial.com/uk/ – they have a tool that will detect what memory your computer has, what the most it can have is and then even sell you the stuff.

Cheers

Danny B

Oh dear. Shakes head.

Does it already have two CPUs? If not then you won’t be able to use the other 8 DIMM slots. That means in order to upgrade you’ll need to replace your current memory with 8 or 16GB DIMMs, 8’s are still usually a premium over 4’s (as in more than twice as much) and 16+GB DIMMs cost a fortune.

Do you need or do you think you need?

Am I the only person wondering why someone needs more than 32gb of RAM? Are you running some serious 3D design software?

What do you call a fat computer that sings?

A Dell

Sorry…………I’ll get me coat

Its a simulations machine, its currently running all 16 cores (2x 8 core processors, HT is off otherwise it would be reporting 32 cores..) but only using about 16gb of its ram, but thats because it needs half of it to move things around in, so with 64gb it will mostly look like its only using 32..

So does anyone know, for this type of application, will using memory that is not exactly the same brand or part no cause any issues?

Am I the only person wondering why someone needs more than 32gb of RAM? Are you running some serious 3D design software?

5 workstations downstairs with 256 😯

There’s a few with 192 aswell now I think about it,

Its a simulations machine, its currently running all 16 cores (2x 8 core processors, HT is off otherwise it would be reporting 32 cores..) but only using about 16gb of its ram, but thats because it needs half of it to move things around in, so with 64gb it will mostly look like its only using 32..

So does anyone know, for this type of application, will using memory that is not exactly the same brand or part no cause any issues?
What kind of Simulations? (Currently sells leading simulation software)
Assume you are running multiple reps in parallel rather than distributing a linear simulation?
The other factor is where do you work, most places use an IT department to buy stuff, otherwise you don’t get it. Guessing you are at uni?

Call the software supplier and ask them it’s what you pay maintenance for(if my phone rings I’m not going to answer)

Mike what software?
Not at uni, but our IT dept sucks, they have no idea what makes a solutions machine, we have budget, and tend to do our own stealth it projects.
Software vendor just recommends more ram, fine we want more ram. I just want to know , does mixing brand or model (even if nominally its the same spec) make any difference?

Why not contact Crucial directly? They sell memory for a living, they should know.

Alternative is a computer broker, don’t know of any good ones currently, but they might be able to get you OE parts.

Yes I spoke to crucial, this is all their fault, they originally told me that, yes it was deadly important to have fully matched modules, which we duly ordered from them. A week later they come back with no stock. Then salesman no 2 tried to convince me that it was not important at all.

They sell memory for a living, they should know.

is not the same as using memory for a living.

So I am seeking clarity from someone who knows..

You’re supposed to used matched pairs for dual-channel configurations (and more for more).

http://en.wikipedia.org/wiki/Multi-channel_memory_architecture

Other than that, no, it shouldn’t make a fig of difference.

Cougar, you are an emodiment of the STW legend. So i can put memory type a in dual channel 1 and b in dual channel 2 will be fine?

I’m not sure I fully understand the question, but the channels should mirror each other. So you’d have type A then type B in channel 1, and type A then type B in channel 2 as well.

Typically on multi-channel mobos the DIMM slots are colour coded. Of course though, there’s no actual standard or consistency as to what those colours mean.

If your board is dual CPU, there’s a possibility that the RAM slots are per-CPU, so you should try and balance the memory evenly across them too. I don’t know how common that is in the workstation world (and the name of the technology escapes me so I’m struggling to google it), but it’s standard in every server I’ve dealt with in recent years. I’d RTFM first if I were you.

The TL;DR version of this I guess is, buy another eight 4Gb sticks and fill up the remaining slots. Then you’re golden even if it turns out you’ve got a quad-channel architecture and CPU-specific memory.

the name of the technology escapes me

NUMA, that’s the bessie. (Thank you, Twitter)

DId you check that all the details match? Just checking the speed (pc12800) isn’t enough. Some systems will need quad rank or single ranked memory plus there are several different voltages. Bit of a minefield to be honest. Looks like dual ranked from the 2R in the part description, but there’s no voltage there from what i can see.

Not at uni, but our IT dept sucks, they have no idea what makes a solutions machine, we have budget, and tend to do our own stealth it projects.

This never ends well……
Seems like you got an answer while it was night here!
My only other tip would be if it’s much cheaper then just replace the lot with new stuff!
I’m selling Flexsim down here in Oz not as resource hungry unless you build it badly!

Mike, thats a little rude, I have been building, installing software, and running pcs since 1997, l’m no expert, but I have yet to have a disaster. If you know anything about simulation you will find that simulations engineers make it their business to try and understand what goes under the bonnet. Thanks to cougar I have a bit more understanding.

I mean from a corporate point of view having been there done it and having a collection of t shirts.

As per retro make sure the various bits match, not just the clock speed. Personally I’d just buy it from Dell as there won’t be warranty issues then either. Also factor in if you fully populate a channel it down-clocks the DIMM speed so you can degrade performance (if memory speed is a bottleneck rather than just more available memory being required), this is why we pay a premium for large DIMM modules on servers so we don’t fully populate

Also factor in if you fully populate a channel it down-clocks the DIMM speed so you can degrade performance (if memory speed is a bottleneck rather than just more available memory being required), this is why we pay a premium for large DIMM modules on servers so we don’t fully populate

I think I need to understand this more?
I thought it was the exact opposite, that if there are empty DIMM slots then there is a portion of the channel that is not being used so its better to spread the memory over every channel rather than concentrate it on one..

IE we have 16 cores and 16 slots so its a essentially a slot for each core..
(I’m bound to be wrong about this, but I would appreciate any help in understanding whats what)

toys19 – Member

Also factor in if you fully populate a channel it down-clocks the DIMM speed so you can degrade performance (if memory speed is a bottleneck rather than just more available memory being required), this is why we pay a premium for large DIMM modules on servers so we don’t fully populate

I think I need to understand this more?
I thought it was the exact opposite, that if there are empty DIMM slots then there is a portion of the channel that is not being used so its better to spread the memory over every channel rather than concentrate it on one..

IE we have 16 cores and 16 slots so its a essentially a slot for each core..
(I’m bound to be wrong about this, but I would appreciate any help in understanding whats what)

Totally depends on the server’s architecture. I had a HP server a while back which had 12 slots per CPU, but to get the absolute fastest performance you need to use two lots of 4xquad ranked sticks for each CPU leaving 4 slots per CPU empty. Whether you need maximum performance or just more capacity depends on your application, more memory might be faster overall even if it is slightly slower (i.e. less swapping, more disk contents cached, DB indexes kept in RAM etc).

The other thing i forgot to mention is ECC. You will almost certainly need that to match what you already have (and it would be silly not to have it on a server TBH).

Why not just phone a couple of IT suppliers and get quotes using Dell’s official part number? You won’t necessarily be able to find places listing the number on google, but loads of people will stock it or its replacement if that part number is EOL.

Totally depends on the server’s architecture. I had a HP server a while back which had 12 slots per CPU, but to get the fastest performance you need to use two lots of 4xquad ranked sticks for each CPU leaving 4 slots per CPU empty.

Yeah, that’s a good point actually. I had one the other week, where if the banks were fully populated the maximum clock speed went down.

The other thing i forgot to mention is ECC. You will almost certainly need that to match what you already have (and it would be silly not to have it on a server TBH).

Correct; though, it’s a workstation not a server.

Its ECC reg, if you read the OP you will note I have the samsung part no.
In fact Dell have confessed this morning that they do not have exactly the same part no memory and they are not offering a solution other than replacing all the memory in one go..

There is no manual – it is a dell branded mother board, they will not give you the info you need on the architecture (or they just don’t know).

5 workstations downstairs with 256

I’ve just installed 6 x DL980s each with 1TB RAM. Data warehouse. And I bet (because of Oracle DBAs) it *still* won’t be enough! 😀

Mike, thats a little rude, I have been building, installing software, and running pcs since 1997

so have I , I still know bugger all about building workstations, not saying you don’t but generally you do get people who have built a couple of home PCs and start knocking up workstations and servers and making a right balls up of it. Normally short term contract staff too, so when they leave it’s IT’s problem.

I’ve just installed 6 x DL980s each with 1TB RAM.

🙄 wouldn’t it be an idea to optimise stuff instead of throwing ram at the problem? (generally i mean)

wouldn’t it be an idea to optimise stuff instead of throwing ram at the problem? (generally i mean)

thats my line and 10/10 I’m right (in my unique software space) they are always the ones who declined training too…

Workstations are a whole different kettle of fish to home PCs!

Different software will be “certified” against particular hardware configurations, and driver revisions.

Getting several pieces of software to work 100% on the same hardware can be a big head ache…

It’s been a while since I looked into it but the frequency down-clocking is a DDR3 issue (not sure if it still exists though and whether some manufacturers have found a way around it) https://docs.google.com/viewer?url=http%3A%2F%2Fwww.dell.com%2Fdownloads%2Fglobal%2Fproducts%2Fpedge%2Fen%2Fserver-poweredge-11g-white-paper.pdf

HP have a ‘Configurator’ app that tells you how to put the RAM in to achieve best performance, but from what you’ve said of your app, NUMA or no, adding the extra RAM will speed it up regardless even if the system as a whole isn’t running optimally.

Have you tried Kingston?

So does all this mean you will be able to watch more porn. That is what computers are for right? 😉

wouldn’t it be an idea to optimise stuff instead of throwing ram at the problem? (generally i mean)

You’ve not met my DBAs or the code the developers write. Its usually cheaper to buy more hardware than to get them to properly normalise their data and improve their packages. Ooer.

They’re moving from a 32-core POWER6 server with 256GB memory which isn’t fast enough apparently, to a dual-RAC cluster on three DL9880s each site running RHEL 6 with 64 cores on each server and throughput of 40GB/s from storage. The things are frighteningly fast (still not sure if can run Crysis or Vista 😀 ).

And they *still* complain. 😆

I’ve a running joke with one of our suppliers, every time I ring she asks if I’m buying a DL980 this time. She’s never managed to sell any.

(It’s not the greatest joke, now that I see it written down)