i7-4790k or i7-5820k for FEA and Engineering Analysis?

December 16, 2014 7:06 PM

I need some help trying to put together another computer system beyond my current machine for primarily performing finite element optimization type tasks and other engineering analysis. I haven’t built a system for long time.

i7-4790k or i7-5820k for FEA and Engineering Analysis

I need some help trying to put together another computer system beyond my current machine for primarily performing finite element optimization type tasks and other engineering analysis. I haven’t built a system for long time. Eventually the machine will become my day to day desktop (currently i7-860). I also need to buy a NAS or a storage server but I think that should be a separate box.

Primary Intended Usage:
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- Small 2D electromagnetic and thermal finite element simulations (generally < 20,000 elements) as part of an evolutionary optimization algorithm. For each generation of the optimization algorithm tens to a hundred independent designs are evaluated making the simulations extremely parallelizable favoring a large number of cores. I am not going to be running these all the time but currently when I do they generally take ½ day to 2 days to complete.

- Matlab simulations

- Solidworks: Relatively simple assemblies

- Rarely some larger scale 3D finite element simulations (generally < 250,000 elements). Maybe very rarely some CFD simulations.

-Eventually the machine will become my day to day desktop as my current machine is a i7-860 2.8 GHz, 8 Gb of RAM, ATI Radeon HD 5700 Series

-I don’t intend to over-clock the machine or play games on it.

The two systems I am thinking about are:
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i7-4790k; $250
ASUS Z97-AR; $90
16 GB (2 x 8 GB) DDR3 1600; $160
Total: $500

i7-5820k; $300
ASUS X99-A; $235
16 GB (4 x 4 GB) DDR4 2400; $200
Video Card: Passive or semi-passive with Display Port and DVI outputs; $150
Total: $885

Components I have Already Purchased:
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Power Supply: Seasonic
Case: Fractal Design R5
CPU Cooler: Coolermaster Hyper 212 Evo
Storage: Crucial MX 100 512 GB SSD (Thinking about exchanging this)

Pluses for the i7-4790k:
Higher base (4 Gz) and turbo (4.4 GHz) CPU frequency than i7-5820k
Relatively in expensive through Microcenter (CPU: $250, MB: $90)
Built in graphics hardware
Low power draw on load ad idle compared to the i7-5820k

Pluses for the i7-5820k:
Two additional cores though they are slower
Twice the memory bandwidth
Maybe more future proof

Questions:
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Which processor and platform is likely to be faster. The i7-4790k has quite a clock frequency advantage while the i7-5820k has two additional cores and twice the memory bandwidth. I know generally for large CFD type simulations a high memory bandwidth is highly recommended. I am not sure memory bandwidth matters much for small finite element simulations though.

Can the memory bandwidth of the i7-4790k and Z-97 be increased substantially by using a higher rated frequency memory and with reduced timings?

Is the additional cost of the i7-5820k and X-99 platform worth it?

I have been toying with the idea of trying to use an Intel Xeon Phi for parallelizing my small simulations further is it likely to work in a ASUS X99-A motherboard in the x16 slot?

What is the likely longevity of the Z-97 and X-99 platforms? I tend to keep computers for a very long time.

Is DDR3 likely to be phased out soon?

While DDR4 while theoretically more future proof I assume the timings and frequency are going to increase rapidly?

Is there a go to low cost video card that is passive or semi-passive with display port and DVI outputs?

Is the built in video card of the i7-4790k, HD 4600, okay for basic CAD work including Solidworks?

Any other thoughts or recommendations on what to purchase?

posted by cycleback to Computers & Internet (7 answers total)

While I can't answer most of your questions definitively, the i7-5820K has almost twice as much cache (15M) as the i7-4790K (8M). Between that, the extra cores, and higher memory bandwidth, it seems like the better choice. Especially if your simulations are parallelizable.
posted by zsazsa at 9:12 PM on December 16, 2014

Parallelization is key to cutting solve time and is probably the most important variable. Make sure each code can solve on multiple cores. Many commercial software packages offer that feature but you must pay for special licenses or tokens. Also, make sure you have enough memory for each type of analysis. If the solver maxes out the available memory, it will start to use the system page file and effectively bring everything to a halt. Your analyses sound very small so I don't think that would ever be a problem for you with 16GB. I doubt memory bandwidth and clocking make a huge difference. Again, parallel processing is the most valuable. Feel free to message me with any questions or further detail. I do FEA for a living.
posted by incolorinred at 9:41 PM on December 16, 2014

I can't really give you any definitive answer, but I would ask: do you know for a fact that the software you'll be running will take full advantage of the extra cores and other fancy features of the CPU?
posted by doctor tough love at 9:42 PM on December 16, 2014

Also, you may struggle using built in video on the CPU to do CAD work. A gaming card is not optimized either for CAD. You really need a workstation solution like a Quadro or you could risk having maddeningly slow redraw rates.
posted by incolorinred at 9:45 PM on December 16, 2014

Response by poster: Some of the code can solve on multiple cores (some versions of the optimization process I have written use open source solvers which I can use essentially in an unlimited manner) while some of the commercial packages cannot.
posted by cycleback at 12:19 AM on December 17, 2014

Get a GPU. Apparently MATLAB supports GPU processing with CUDA.
posted by I-baLL at 8:28 AM on December 17, 2014 [1 favorite]

Multiple processor cores will not help with Solidworks, unless you are doing FEA in Solidworks in which case it will. Raw processor speed is the most important for SW. Like incolorinred said, a 3D card for CAD will give better results but may not be necessary for what you need. Unless you have large, complicated assemblies (think >100 parts with intensive features like screwthreads) a gaming video card will probably be acceptable.
posted by Dmenet at 3:03 PM on December 18, 2014