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August 13, 2010 5:22pm UTC in response to Anna Cyganowski

Re: What would be your ideal COMSOL workstation?

well i did the same last year mostly because i was bored.. I wont do it again...
So let me give you my thinking
1-Choice of OS: linux not windows because of the openess and ability to tweak machine performance more easily. the only minus I can think of nt using windows is that if you also need to use a "windows only" soft coupled with comsol ...
2- memory size depends the size of your problems 1GB is NOT ENOUGH.. think for 3d specially you should think along the line of 24 GB AT THE VERY least or 64 GB if you can afford it .
you will then get a dual proc mother board.

I spoke about a comsol person at the time of the building and she told me that for processor, high clock frequency was the parameter to favor when the budget was constrained.
in the end you end up with 8 or 12 cores machines depending upon your budget

and YES YOU WANT 64 bits to address all the memory you will use for 3d simulations. Nobody today will seriously consider buying a new 32b its workstation for scientific computing

with linux the graphic part can be tricky for you have to met comsol requirement strictly [ Open GL driver and so forth.. ] but it is pretty well documented on their website

3 why do I think it is a bad idea... ?
speaking from experience...
building your own machine still represent a significant budget.
what you dont do well usually, if you dont build pc on a regular basis, is thermal engineering..[ putting compnents and wiring them is rather trivial otherwise nwadays...
but in the end you wil end up with either an overheating machine [ very bad and potentialy destructive] or a very noisy one [bad] as in my case... I had to put the UC in another room form my office just because of the fan noise...

SO You better go to a local pc dealer and tell him what you want and he will do it for you or just use the "customize feature" that most major manufacturer propose on their website....for you the cost will be in the end the same or possibly less compared to as if you buy the components say on amazon
and you will have for sure a better machine and a warranty ...much less headache risk and time wasted...

JF

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August 15, 2010 8:44am UTC in response to Andras Gilicz

Re: What would be your ideal COMSOL workstation?

Hi

to add a little, for me the ONLY reason I also have a Windows OS (Win 7 recently) is to have the LiveLink to SolidWorks, as my CAD models come often from my colleagues, and I do not want to redo everything and SW runs onlyunder Windows.
Furhtermore I can do shape optimisation easily.
For that other points I agree with François. Mac or Linux/Unix for me is the same issue. I have a dual boot, hence I can use both, but I notice not that great differences, UX seems superior once the system start to swap RAM to disk.

For the RAM and CPU's, I would say definitively as much RAM as possible, BUT high speed RAM, and check carefully the bottlenecks on RAM to cach transfer, where systems like this sits and wait for access the most of the time. A 3D model uses easily dozen of GbRAM, and in this case 64-bit is required to address it.

Then it's better to have as many cores as possible, as this distributes the RAM on their local cache and a maximum of parallelism can be achieved, on the same PC COMSOL runs on what is available of parallel cores, when possible (but not always then the single CPU running is giving the pace)

I have tested the multiple cores on my PC 2x6x2 cores-multiplexed, or 2x6 standard, I see little differences, perhaps slightly better in 2x6 than 2x6x2-multiplexed (Idid this with the -np command, not via the BIOS cold still be an issue. In anycase under win-7 one core is mostly used by the OS

For the graphics, a recent Nvidia GPU car with sufficint RAM is OK, but upload the latest BIOS, it anyhow not that expensive today

Buid or buy: I'll prefer to buy you can get "big" WS if you look carefully on the advertisements, then it's often cheaper to buy

Last: a high speed disk for efficient swapping (I have three, one for each OS + swap, one for the soft and the users and the scratch

--
Good luck
Ivar

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August 16, 2010 4:30am UTC in response to Davis Sentman

Re: What would be your ideal COMSOL workstation?

@David re "open source"
Open source "per se" is irrelevant of course...
but because of the "open source spirit" you are provided with options that windows, to the best of my knowledge, [not sure about mac] dont provide ..and that can, depending upon your need, impact significantly your computing performance when you know what you are doing.

One example: swap file
on my machine all my user disks partitions are raid 1 for redundancy [regular read/ write on disk have marginal impact on performance for me so I dont bother going with a more sophisticated raid configuration] but my swap files are distributed along all my drives in a "raid 0" mode [a standard option with most linux distro]designed for maximum bandwidth when you hae to access the swap files. I have a total of 4 drives so it make a LOT of difference when comsol has to use VM.
Not sure how you will do that with windows.

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August 17, 2010 11:53pm UTC in response to Davis Sentman

Re: What would be your ideal COMSOL workstation?

Thank you all for your helpful responses!

In order to save costs, another idea I had was to use the Amazon EC2 -- does anyone have any experience using COMSOL with the cloud? Would there be any strong negatives to using the cloud instead of local hardware?

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November 1, 2010 1:26pm UTC in response to Ivar Kjelberg

Re: What would be your ideal COMSOL workstation?

About the fast hard drive: Is there a reason to buy a SSD for swapping?

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November 18, 2010 10:10am UTC in response to Daniel Krebs

Re: What would be your ideal COMSOL workstation?

Hi
for me most advanced graphical cards should do and a few hundred Euro is not the most expensive, be sure yu have a "CAD" card and not really a Gaming one video and CAD graphics are not fully the same thing, but today most graphical card do no longer have this distinction. But I must admit have a FX8500, not 580 as I'm working now on two high res screens, and that is really comportable, the ROI is rapidly there when you spend hours behind your screen

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Good luck
Ivar

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January 5, 2012 2:09pm UTC in response to Ivar Kjelberg

Re: What would be your ideal COMSOL workstation?

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