32 gb ram with z68?

[spanz]

Excuse the newb question, but I am just getting started with OCing. I am planning a number crunching workstation, and have decided on an I7 2600K on a z68 motherboard (like a P8Z68-V Pro or GA-Z68mx-UD2H-B3). These boards list the ram as "32 GB max". So when I look around for 4 x 8 GB dimms to fit it, I do not find any. I come up with things like 4 x 4GB for 16 GB total.

Does ANYONE make 4 x 8 GB dimms yet for these boards and overclocking?

 

[jaquith]

The 8GB, very few non-ECC, are for most people cost prohibitive. Samsung makes them -> http://www.discountmicrosales.com/m378b1g73ah0-ch9.html I assume others will follow.

So if you're planing on a normal Workstation {Xeon, ECC RAM, etc} then you'll need a Server MOBO.

 

[spanz]

Ho jeez! $780 for one 8 gb stick!

If I understand what you are saying, go with a server board where there are many more than 4 dimm slots, so then I can use more normal memory dimms?

But does someone make a server board or workstation board that would run with the I7 2600K and overclock it, or am I doomed to using a high priced Xeon cpu then?

 

[jaquith]

The server boards don't run consumer CPUs, and server boards like the LGA 1366 that can OC by the BCLK. CPU speeds -> http://www.cpubenchmark.net/high_end_cpus.html and OC results -> http://www.cpubenchmark.net/overclocked_cpus.html

If you're critical number crunching then there no way you want to OC, and you only want ECC.

Q - What are you trying to do?

 

[GhislainG]

Ho jeez! $780 for one 8 gb stick!

If I understand what you are saying, go with a server board where there are many more than 4 dimm slots, so then I can use more normal memory dimms?

But does someone make a server board or workstation board that would run with the I7 2600K and overclock it, or am I doomed to using a high priced Xeon cpu then?

Instead of an I7-2600K, you probably should use a Xeon E3-1200 Series processor and ECC UDIMM memory on a motherboard like the ASUS P8B WS. I haven't found any socket 1155 motherboard that has more than 4 memory slots. You should check the QVL to make sure that 32 GB (4 x 8 GB) of memory has been tested. You'll have to check the motherboard manual to find out if overclocking is posssible or not.

 

[spanz]

Instead of an I7-2600K, you probably should use a Xeon E3-1200 Series processor and ECC UDIMM memory on a motherboard like the ASUS P8B WS. I haven't found any socket 1155 motherboard that has more than 4 memory slots. You should check the QVL to make sure that 32 GB (4 x 8 GB) of memory has been tested. You'll have to check the motherboard manual to find out if overclocking is posssible or not.

I run a number of engineering programs, like altium board layout, solidworks mechanical design, sonnet electromagnetic analysis, agilent genesis. I have an e8400 with 16 gb ram, and I recently ran an RF analysis of a much simplified circuit that took 28 hours to run, for instance. I need something faster!

As far as the p8b ws, ecc udimm memory does seem to be more available. Let me look into that.

 

[spanz]

So going from 2 cores at 3.3 ghz to 8 cores at 3.5 ghz should take my 28 hour analysis and make it more like 5 hours. But then I would be tempted to analyze a bigger area of the circuit board, and the analysis time would go right back up. Hence the desire to overclock (to maybe 4.2 ghz or so). The apps are not that graphics oriented, an nvidia q2000d graphics card is adequate for me.

 

[spanz]

p8b ws memory does ecc, but comes with this note: "Non-ECC memory only support for client OS (Windows7,Vista and XP)"

I would be running windows 7 64 bit, so again stuck with only non-ecc memory, and the gigundo price tag for 32 gb at samsung.

 

[compulsivebuilder]

I looked up the QVL at ASUS for the P8B WS motherboard. There are two 8GB DIMMs listed - the Samsung and the A-Data. I found a huge price for the Samsung; couldn't find a price for the A Data.

Right now, 8GB DIMMs are not a practical choice. Motherboards are starting to include support, but 8GB DIMMs are not being made in any quantity, so they cost a fortune. Part of the reason they are expensive is because they are effectively two 4GB DIMMs in parallel - they have twice as many chips on them as regular DIMMs.

How long before 8GB DIMMs are available at rational prices? Good question - I'd like to know, too Bear in mind that it wasn't much over a year ago that 4GB DIMMs were uncommon - now they are so cheap that they are an obvious choice.

 

[compulsivebuilder]

So going from 2 cores at 3.3 ghz to 8 cores at 3.5 ghz should take my 28 hour analysis and make it more like 5 hours. But then I would be tempted to analyze a bigger area of the circuit board, and the analysis time would go right back up. Hence the desire to overclock (to maybe 4.2 ghz or so). The apps are not that graphics oriented, an nvidia q2000d graphics card is adequate for me.

The i7 2600K isn't really 8 cores; it's 4 cores + hyper-threading. Hyper-threading works great for a lot of applications, especially I/O bound ones. Not so great for CPU-bound work. I think you'll find it will run more like 4 cores for you, rather than 8.

It is possible that the older (and much more expensive) i7 990X six core CPU might work better for you. It goes onto an LGA 1366 motherboard, and you can fit 24GB of RAM using 4GB DIMMs.

I wonder what kind of number-crunching is involved - I don't know much about the kind of analysis you are describing. Could it use something like CUDA instead? Maybe you could offload it to a powerful GPU? For some kinds of processing, you might see a huge advantage in processing on the GPU instead of the CPU.

 

[jitpublisher]

This sounds more like a very poorly written program than a hardware problem.

 

[GhislainG]

p8b ws memory does ecc, but comes with this note: "Non-ECC memory only support for client OS (Windows7,Vista and XP)"

I would be running windows 7 64 bit, so again stuck with only non-ecc memory, and the gigundo price tag for 32 gb at samsung.

Windows 7 Professional or Enterprise? Other versions are limited to 2, 8 or 16 GB.

http://msdn.microsoft.com/en-us/library/ff559390%28v=vs.85%29.aspx implies that Windows 7 supports ECC memory. Asus probably meant that they don't recommend more than 16 GB of non-ECC memory. If you really need a lot of processing power, then why not use a server motherboard with 2 or more processors on this list? http://ark.intel.com/ProductCollection.aspx?codeName=33175

 

[jaquith]

p8b ws memory does ecc, but comes with this note: "Non-ECC memory only support for client OS (Windows7,Vista and XP)"

I would be running windows 7 64 bit, so again stuck with only non-ecc memory, and the gigundo price tag for 32 gb at samsung.

I 'think' this may be referring to non-Xeon CPUs that the ASUS P8B WS also supports, so I'd verify with ASUS.

I know Windows works perfectly well with ECC and some Windows Server 2008 environments e.g. Hyper-V requires ECC. In my office the servers run RHEL x64 and all are ECC + Xeons.

Another option are the LGA 1366 consumer {6x4GB 24GB} or dual server {18x4GB 72GB or 18x8GB 144GB registered ECC}.
SUPERMICRO MBD-X8DAH+-F-O http://www.newegg.com/Product/Product.aspx?Item=N82E16813182177
ref - http://www.supermicro.com/products/motherboard/QPI/5500/X8DAH_-F.cfm
os - http://www.supermicro.com/support/resources/OS/5500.cfm
RAM http://www.crucial.com/store/listparts.aspx?model=SUPER%20X8DAH%2B-F&Cat=RAM
each 3x8GB kit is $800, and you can get 16GB stick 3x16GB is $1900

 

[spanz]

Dual xeons on a workspace mobo are the way others using these programs are going. But we are talking 2 x $600+ for the cpu, while the I7 2600K is an unbelievable bargain. I just do not have the bux at this time, but still need to do the work.

If the darned i7 990 or 980 did not cost a fortune...that would be an option too, but it seems like ~ obsolete technology that is soon to be replaced.

Yeah, I was thinking that the hyperthreading would act like more cores in the I7, but until I actually run the machine, don't know how the software would react. It might only act as 4 cores.

I guess the real question is: why don't the motherboard makers give us boards that can hold 8 dimms?

 

[compulsivebuilder]

I guess the real question is: why don't the motherboard makers give us boards that can hold 8 dimms?

Why not? Because few people need more than 4 DIMM sockets on a general purpose PC at the moment, and it's easier and cheaper to build the CPU to handle 2 x 2 DIMMs. To support more DIMMS, you need to introduce additional logic.

 

[jaquith]

The current LGA 1155 Sandy Bridge lacks the pins for any thing more than 4xDIMM. The newer SB-E is Quad Channel but you're stuck until Nov~Dec.

There are cheaper LGA 1366 Xeons, keep in mind a Dual CPU is not a comparison to a single CPU. Yep, it's all about the money but it's also about the processing environment. I'd run Dual E5620 and fill it up with 4GB sticks.

$590 Intel Xeon E5645 Westmere-EP 2.4GHz 6 x 256KB L2 Cache 12MB L3 Cache LGA 1366 80W Six-Core
$390 Intel Xeon E5620 Westmere 2.4GHz 12MB L3 Cache LGA 1366 80W Quad-Core
$285 Intel Xeon E5607 Westmere-EP 2.26GHz 4 x 256KB L2 Cache 8MB L3 Cache LGA 1366 80W Quad-Core

 

[tinkererguy]

Things are improving, with 8 DIMM slot Sandbridge-E (X79) seemingly driving the release of a bunch of memory kits from various vendors. The 32GB (4 x 8GB) kits can be used by 4 DIMM slot Sandybridge (Z68) systems, at roughly $500, see more details at
http://tinkertry.com/32gb