Building custom render rig. 6 GPUS

[JessicaVines]

Considering building a render rig with 6x 580 3gb, sourced second hand. This is in preparation for V2 so will likely operate over Ethernet. I want to run stock air coolers so I am prepared to build a bitcoin style setup with GPU risers in a custom wood frame. A few questions....

1) I want to confirm that running 1X pci won't affect card performance, only scene load time which will be bottlenecked by Ethernet anyway it seems.

2) active vs passive risers. Has anyone had any experience?

3) what do we know about out of core rendering? Does it literally nullify VRAM? Will it then become crucial to have fast Bus pci speed eg 16x.

4) how should I power this safely? 2 medium power supplies or 1 huge power supply?

5) how important is system memory? And cpu? Should I shoot for 32 gb? Do I need to get a beasty cpu too?

6) any mobo recommendations that won't blow my budget. Chipset?

Thanks.

[glimpse]

hi, Jessica.


nice to see Guys are prepping for v2 =)


1. Yeah X1 is not is not going to erode any of rendering performance, only load times.

2. as far as I understand active risers are needed to split lanes - divide one conection into 2,3, 4 or more.

(You should always look like that: more parts, more places to fail for something, especially if You're trying to build a rig on budget. Keeping things simple will help You to avoid future downtime 'caused by something malfunctioning, that might be hard to track right away)

3. No it will not nulify vRAM, as only the part of data could be stored that way, pluss it's not comming right away

(but that's only what I understood so far 'bout this topic. I remember there were some thread in the forum where dev's answered this question)

4. 580 will eat around 250 (depending on a version You have)..You might be able to find PSU that would be capable to deliver 1.7-2Kw, but I wouldn't be surprised to see those priced higher being a nishe product.

Probably getting two power suply and conector for 24pin to power them up with one button would be cheaper. As You don't need to think 'bout space I don't see the point running one PSU.

5. There's sort of unwritten rule here to have 3,4 times more of system RAM compared to vRAM on GPU as some proceses migh need taht much RAM. So in case of 3Gb 580s You should be able to run just fine with 16gb, especially for slave as You'll not be eating RAM for with any other software.

For CPU dropping cheap quadcore is more than enough.

6. If You're running on the budget, might be even better to get something like 4cards per mobo, as 6 will narrow down models You can choose from. Some companies start making simple boards with not so much of features http://www.tomshardware.com/news/asrock ... 25092.html (think someone already have this model in the forum, You can take a look & ask for oppinion)

[slepy8]

maybe you'll find some answears here:

http://render.otoy.com/forum/viewtopic.php?f=40&t=39500

[whersmy]

Pretty much what Glimpse summed up.

I can tell you that a good psu is very important. You don`t want to skip that. Ofcourse second hand psu`s can still be reliable.

[FrankPooleFloating]

Jessica, do a price comparison between Intel build and AMD... there is one good 4-GPU (6 PCI-E) AMD board: GIGABYTE GA-990FXA-UD7.. this bad-boy with maybe a AMD 8350 Black Edition would be hundreds less than a comparable Intel workstation. If you went with the UD7, be sure to get Rev 3, since the older ones had some serious problems.

[whersmy]

Yep! Do a good reading on the version of mainboards and support. I once bought a server board only to find that it just only supported quadro cards....

[JessicaVines]

Thanks so much guys, this is a great help.

I'd love to have a read of the out of core rendering thread. I couldn't find much about it in my search.

I am just trying to squeeze as much power as i can under one box so I won't have to invest in many Octane licenses. As of today we are told that Octane 2.0 render slaves will require a full standalone license which seems fair i guess, just means i have to reshuffle some ideas of my build.

As for the mining rig layout. This is simply because I really dont like the idea of having stock 580's right up against eachother. Im told the're demonically hot (and noisey!) but very effective performance/price ratio at the moment.

Kind regards.

[daveyt]

Hi Jessica,
I'm also very interested in building a bitcoin style rig, I found this interesting http://www.youtube.com/channel/UCVVWXoQfMfQVuzxcLylq9aA
Would like to Know how your progress goes.