Liquid cooling for Z840?

[GTWatson77459]

I currently have a Z800 WS with dual Xeon CPU's and liquid cooling.  I'm scheduled to get a new WS and was looking at the Z840 but I don't see a Liquid Cooling option. I run Structural Analysis software that lets me analyze one load case per core so more cores means faster throughput.

I've been told the fastest clock speed and multiple real cores will be best, so what CPU and RAM will work best? 

Another question, does HP have a Mobo that supports multiple consumer i7 cpu's with lots of ram? I'm not sure if the Z840 WS and Xeon cpu is the best bet.  Are there other options? 

[MSLEEE · Accepted solution]

There is no liquid cooling option for z840 systems. With current processors, we do not think the system requires the liquid colling option. HP is going to release a high performance air cooling kit instead of the liquid cooling. I do not know when but not long.

The following quicspecs list the supported processors and memory modules. This system supports INTEL® XEON® E5 and DDR4-2133 ECC Registered/ Load Reduced (LR) RAM . 

http://www8.hp.com/h20195/v2/GetPDF.aspx/c04400043.pdf

For the performance, this is not the simple question. It depends on your applciation such as CPU-intensive, memory intensive, disk-intesive, or other intensive applications.

[Dan_WGBU]

GTWatson77459 wrote:

"Another question, does HP have a Mobo that supports multiple consumer i7 cpu's with lots of ram? I'm not sure if the Z840 WS and Xeon cpu is the best bet.  Are there other options? "

Consumer and Xeon processors have several important differences.  The consumer i7 CPUs do not support dual (or more) CPUs on the same motherboard because they do not have the extra QPI links that are used for CPU-to-CPU communication.  The E5-26xx Xeon CPUs have an extra QPI link that supports 2 CPUs on a motherboard, such as the HP Z8xx and Z6xx systems.  FYI, servers use the E5-46xx Xeon CPUs that have more QPI links so they can connect 4 CPUs per motherboard. 

The HP Z840, Z640, and Z440 also have 4 memory channels per CPU.  This allows memory to be accessed from 4 sets of DIMMs at the same time, which significantly increases memory bandwidth.  Most consumer CPUs have 2 memory channels, so they have both fewer memory slots and have less memory bandwidth.  This is a difference between some Xeons and consumer CPUs. 

Another way to reword your question could be:  "What are the differences between a Workstation and a high performance consumer system?"  The answer is dual CPU sockets, CPU cores, more memory slots, higher memory bandwidth, more expansion slots capable of supporting dual or triple graphics cards, higher power supplies, etc.  If your applications take advantage of these capabilities, then a Xeon workstation will outperform consumer systems. 

[GTWatson77459]

Thanks for the replies and the link to the spec sheet.

When running the Tower Line FEM software, there are a few seconds where all cores ramp up and run one load case each out of around 100 load cases so the more fast cores the better. Once all the thousands of equations are solved, it drops back to a single core to do the reporting and writing to the screen.

I rarely do big building type projects but normal I7 type pc's can run the structural FEM software for several hours while doing dynamic analysis of building frames for earthquakes.

The many options of CPU, memory, graphics cards, looks very confusing for an old Structural Engineer to comprehend.  Our budget for PC's got cut until next year, so I have some time to wait and learn.

[Dan_WGBU]

GTWatson77459 wrote:

"The many options of CPU, memory, graphics cards, looks very confusing for an old Structural Engineer to comprehend."

I agree, it is confusing.  Does your structural FEM software vendor have any suggestions or recommendations on the type of hardware that will work best?  I assume this software is an expensive, professional package. 

[GTWatson77459]

I talk or eMail them and I devised a test problem that I ran on my old Z800 and they ran on an overclocked i7 that beat me (1.13 seconds vs 1.5 seconds) to run 300 load cases. The report writing and graphics displaying took another few seconds.  When doing the graphics, their overclocked i7 running one core was faster than my 12 core Z800.

I have the figures on my work PC and can look them up.  Our IT people would never let me overclock a work PC, so I am stuck with whatever comes out of the box.  They did advise that if I got the Z840, I sould get the SSD and fill up all the 16 ram slots with 4 gB DIMMS.  IIRC, their software reads config files from the C: drive and saves temp files to the C: drive, plus the program loads from the C: drive so the SSD should be much faster than the old spinning HDD's I have now.

[Skylarking]

You can't simply compare one CPU from one generation with another CPU from a different generation. And comparing some overclocked i7 to some xeon without knowing the i7 specs and xeon specs, especially when the i7 is overclocked, is less than helpful.

Basically your software vendor should know their software inside out and should be able to advise where any performance bottlenecks may occur, be it CPU or memory or PCIe/GPU processing or storage (HDD/SSD/etc). They wrote the software and should be able to advise the best system and OS to make most efficient use of what is likely a rather costly application.

And I assume the most useful feature when doing structural analysis is that Xeons can use ECC memory and thus your results should be less suseptable to memory related errors (that may or may not be picked up by the software/os when using non ECC memory).

But then again i'm not an expert so i'd look towards your software vendor of rationalised advice.

Oh, and i'd also avoid any overclocking unless you also want to handle your own workstation hardware maintenance!

[SalSimp]

Just saw your post ... I have a Z840 that I have upgraded to E5-2667v3 processors. Those consume 130 Watts each so I wanted to upgrade to liquid cooling basically to find out it was not available. But on closer look, I noticed that the Z840 motherboard had similar pin connectors (and in the same location) for liquid cooled heatsinksas my Z820. The only difference being the Z840 has a 3-pin header while the Z820 has a 4-pin header. The liquid cooled heatsinks for the Z820 have a 4-pin plug but only three have wires in them. So I decided to install them on the Z840 and connect the 4-pin plug to the 3-pin header leaving the empty header position off to one side (blank). AND, they work!

The fans showd is no problem since it is the same as in the Z820 ... So I am running a Z840 with liquid cooled heatsinks.