Motherboard recommended for 4 cards?

[smicha]

Without water cooling, I am not sure I would just have 4 cards stuffed in a case. In that config, the middle cards will hit like 90c almost instantly.

Yes - and will loose 40% of rendering power compared to watercooling config.

I am not entirely sure what you mean by that. All cards run @ 1020 ghz on the processor averaging about 60c... I am cranking 1K samples a second on my current simple scene...

EDIT: Most importantly, for the cost of a water cooling rig / blocks you can buy 3 more cards. /shrug

When you put 4 cards on air they will run at 700-900, on water 1200-1300 mhz.

As for costs - about 700-1000EUR for cooling down 4 cards.

[gazukull]

Oh my bad, I though you meant on risers.

[smicha]

Oh, on raiser yes - they don't slow down that much

[Tos]

Hi everyone,
sorry for the little bump.
Recently I bought an Asus X99e ws, but I'm having problems with pcie usb3 1xto16x risers.
I tried 5 video cards (1 gtx 980 and 4 780 6gb) and they just don't seem to work, they gave me a lot of random fatal errors, chassis intruded, overclock failed and so on during boot. Sometimes the system boots correctly, but I still did not manage to have all the 5 gpus working at the same time.
Then I switched all the gpus to an old p8p67 evo and everything works fine.
Is my board defective or the x99-e ws does not support that kind of risers?

[glimpse]

if You buy such expensive motherboard like that ASUS WS - don't use cheap risers - get some proper stuff 16x quality pieces that will cost You slightly more..but..it's well worth.

Just to mention You need shielded cables in order to have stability as PCIe signals going through are very sensitive..learn from Guys who made this before : Going on Air wide open - custom rig for Octane Render by Polder animation

[Tos]

Hey glimpse,
I've already read your article (I like your blog btw). I forgot to say that I also tried with 16x to 16x shielded risers with same poor result.

[glimpse]

Hey glimpse,
I've already read your article (I like your blog btw). I forgot to say that I also tried with 16x to 16x shielded risers with same poor result.

ghm, maybe it's faulty motherboard..- does it work fine with up to four cards seated directly ???

[Tos]

I tried with 3 cards directly connected and it works, but when I connect one riser (shielded, powered) it starts with those crazy errors on boot.
On another motherboard all the gpus work ok with risers (both 16x-16x and 16x-1x) so I don't know what to think.

[glimpse]

I tried with 3 cards directly connected and it works, but when I connect one riser (shielded, powered) it starts with those crazy errors on boot.
On another motherboard all the gpus work ok with risers (both 16x-16x and 16x-1x) so I don't know what to think.

from what I already seen some motherboards are very sensitive to those - blue screens happen more often when You plug ribbon cables or other extensions - some Guys find useful to test several different pieces - but I haven't seen any consensus on this..-for some work one thing for other other..

faulty mother board might be a thing, but I don't see RMA point here as it works fine with 3x cards directly plugged..-so Guys from company might say: it's Your risers..

Have You plugged additional 6pin power plug to motherboard? (just above those PCIe slots?) - seen some Guys running without it - in multi GPU situations it's highly advisable to have it as it provides additional power - some stabilities issues might be solved this way..

[caffe3]

How about 4x Titan X superclocked inside a Cooler Master HAF X (it has a fan on the side of the case aimed at the gpus as well as one in the middle of the case, also aimed at the gpus).

The nvidia Dev computer has aircooled titan x. So a case like HAF X with 2 extra fans directly on the gpus should be pretty solid, no?