[Ruli]

Hi guys,
first of all, I am sorry if I annoy you with just another question about PC specifications, but slowly I am getting lost in the swamp of CFD-compatible hardware.

I want to buy a new PC/workstation for my soon to start MA thesis (wind turbine simulation) and later work, which should be suitable for CAD (Rhino or Inventor), MATLAB and especially for OpenFOAM. My budget lies around ~1000€, ~1500€ if necessary or sensible.

OpenFOAM I use for:

• aero-/hydrodynamic simulation
• maybe moving mesh
• snappyHexMesh, approx. 4 to 10 Mio. cells
• simpleFOAM, pisoFOAM, pimpleFOAM, interFOAM
• DES or RANS

In the last days I read a lot of reviews and benchmarks of PC hardware. I tried to find a good compromise between high performance, silent hardware, good cooling, fast hard disk and low price (often I tried to pick the best price-to-performance-ratio). This is the result:

• Case: NZXT H630, with USB 3.0, lots of space inside (also for coolers) 133€
• Motherboard: ASUS Z87-Pro (C2) 157€
• CPU: Intel Core i7-4770K, Quad-Core Haswell, 4 x 3.5GHz 287€
• RAM: Kingston HyperX 10th Year Anniversary Edition DIMM XMP Kit 32GB, 4 x 8GB, DDR3, 1600 MHz 284€
• GPU: Inno3D iChill GeForce GTX 760, 2GB GDDR5, CUDA 260€
• SSD: Samsung SSD 840 Pro, 256 GB 188€
• Hard Disk: Seagate Barracuda 7200.14, 3TB 99€
• Power Supply: Enermax MODU87+ 600W ATX 2.3, 600W 163€
• Several coolers

I think, the system does not sound too bad, there is just one problem: In total I calculate a price of about 1750€....


My questions are:
-Q1: Do you think the system is suitable for the mentioned purpose?
-Q2: Where do you think can I save some money?


I am thankful for every tip and comment.


Thank you
Julian

[wyldckat]

Greetings Julian and welcome to the forum!

OK, here's what I would trim down:

• GPU: pick a cheaper card, near half the price or even in the ~100€ range. The 760 is overkill for just 10 million cells.
• Motherboard: usually I pick motherboards almost on intuition... what matters is if SATA/DDR and Chipset are all good enough to run! And 120€ worth should be more than enough.
• RAM: 16GB should be enough for 10 million cells.
• CPU: OpenFOAM does not take advantage of multi-threading. And the K edition is only worth it if you over-clock. If not, choose one of the pure quad-core CPUs.
• SSD: 256GB? 60GB is more than enough for the operating system and handling one or two cases at a time.
• And the 3TB drive should be fast enough for what you need. But be sure to pick one of the drives that is meant for proper operation, not one of the low energy ones... if you want speed, that is. Example: Western Digital has the Green, Blue, Black editions, in increasing performance ranges and energy expenditure.
• That power supply is a bit of an overkill, cost-wise. You should be able to get one for half the price, such as a "CORSAIR TX650 V2 - 650W 80 PLUS BRONZE".

Best regards,
Bruno

[Ruli]

Hi Bruno,
thanks for your fast reply and for the tips.

Originally Posted by wyldckat

GPU: pick a cheaper card, near half the price or even in the ~100€ range. The 760 is overkill for just 10 million cells.

I had the same thought. As the GPU should be suitable for other purposes (games, CAD, Engineering software), too, I chose this one as an alternative:

PNY GeForce GTX 660 XLR8 Edition, 2GB GDDR5, 2x DVI, HDMI, DisplayPort (GF660GTX2GEPB) 171€

Originally Posted by wyldckat

Motherboard: usually I pick motherboards almost on intuition... what matters is if SATA/DDR and Chipset are all good enough to run! And 120€ worth should be more than enough.

What aspects of a motherboard do I have to take care of for a CFD-PC?

Originally Posted by wyldckat

RAM: 16GB should be enough for 10 million cells.

I had the same idea after some research

Originally Posted by wyldckat

CPU: OpenFOAM does not take advantage of multi-threading. And the K edition is only worth it if you over-clock. If not, choose one of the pure quad-core CPUs.

Good to know! I found this one:

Intel Core i5-4670K 192€

Originally Posted by wyldckat

SSD: 256GB? 60GB is more than enough for the operating system and handling one or two cases at a time.

I am planning to install Ubuntu virtually under Windows 7. Plus I want to install lots of big software packages on the SSD. Therefore I think, 256GB should be good.

Originally Posted by wyldckat

And the 3TB drive should be fast enough for what you need. But be sure to pick one of the drives that is meant for proper operation, not one of the low energy ones... if you want speed, that is. Example: Western Digital has the Green, Blue, Black editions, in increasing performance ranges and energy expenditure.

I will think about it.

Originally Posted by wyldckat

That power supply is a bit of an overkill, cost-wise. You should be able to get one for half the price, such as a "CORSAIR TX650 V2 - 650W 80 PLUS BRONZE".

I chose this one because of the high efficiency. My idea is, as the PC will run a lot, that I save money one the long run this way.

Anyway, thanks for your hints. Any more suggestions?

Bye
Julian

[wyldckat]

Hi Julian,

Originally Posted by Ruli

PNY GeForce GTX 660 XLR8 Edition, 2GB GDDR5, 2x DVI, HDMI, DisplayPort (GF660GTX2GEPB) 171€

It's your money and your fun that is on the line here!

Originally Posted by Ruli

What aspects of a motherboard do I have to take care of for a CFD-PC?

High memory and PCI performance and SATA performance. In essence, check what chipset each motherboard has got for the values you have in mind and do some searching about that chipset. So chipsets only have additional SATA ports or SAS or RAID controllers, so they end up not being worth the price.
Wikipedia to the rescue: http://en.wikipedia.org/wiki/List_of...eries_chipsets

Originally Posted by Ruli

Good to know! I found this one:

Intel Core i5-4670K 192€

[...]

I am planning to install Ubuntu virtually under Windows 7. Plus I want to install lots of big software packages on the SSD. Therefore I think, 256GB should be good.

OK... if you're planning on using a VM and Windows, I strongly suggest that you switch to an i7 instead This way you can use 4 cores for the VM and the remaining threads can come in handy for keeping control over the real machine.

But honestly, I suggest that you choose one of the following solutions instead:

1. Use a Linux Distribution for the real machine and put Windows inside a VM. Although you probably want to run games on Windows....
2. Use dual boot. When you need to do work, use a Linux Distribution. When you want to play, use Windows. You probably wont have enough CPU power available to do both at the same time either way.
3. Last but not least, if you don't like (or don't want) to use a Linux Distribution, might I suggest blueCFD: http://www.bluecape.com.pt/blueCFD - it's an unofficial port of OpenFOAM for Windows, which brings to Windows most of the open source software related to OpenFOAM. Disclaimer: I'm the guy responsible for its development.

Originally Posted by Ruli

I chose this one because of the high efficiency. My idea is, as the PC will run a lot, that I save money one the long run this way.

I know the feeling. Problem is that power efficiency only reduces the temperature and a bit of the power consumption, as well as minimizing electric interference on the other house's electric appliances. Therefore, it strongly depends on how long the machine will be turned on and for how many years.
Unfortunately I don't know of any specific benchmark on power/cost savings with such power supplies

Best regards,
Bruno