7 GPU configuration - will this work for GPU-RT

[Delineate]

Hey everyone... 3 questions here.



1. Since RT doesn't rely on SLI, In theory on a 7 pci-e connection motherboard, would the above work for VRAY RT GPU?
2. Recommend GPU's for this purpose... or do you recommend waiting for the Kepler series which I assume will burn a nice big hole in my wallet.
3. If this was to be a render node with 2 Gigabit ethernet ports, how much slower would this be in comparison to running the configuration locally on the 3dsmax workstation.

Vlado & the Chaos group guys, do you have experience with this sort of arrangement? And is there a point where too many GPU's stop being beneficial.

Thanks in advance!!
Cheers!

[vlado]

1. Since RT doesn't rely on SLI, In theory on a 7 pci-e connection motherboard, would the above work for VRAY RT GPU?

Yes, it will work.

2. Recommend GPU's for this purpose... or do you recommend waiting for the Kepler series which I assume will burn a nice big hole in my wallet.

There are many possibilities here, depending on your budget. Hopefully someone else will have more info for you.

3. If this was to be a render node with 2 Gigabit ethernet ports, how much slower would this be in comparison to running the configuration locally on the 3dsmax workstation.

The time to transfer the initial scene and start rendering might be longer, depending on your network speed. For the actual rendering, there ways to control the nework traffic, so it's not so much of an issue.

Vlado & the Chaos group guys, do you have experience with this sort of arrangement? And is there a point where too many GPU's stop being beneficial.

Seven will work fine But it would be best if you can test this setup before spending money on it. For example, some motherboards have issues when so many GPUs are attaches.

Best regards,
Vlado

[Delineate]

Sounds promising then Vlado, thanks for that! I might use the motherboard as illustrated here https://bitcointalk.org/index.php?topic=34174.0 as its proven to work.

One more questions popped into my head, maybe someone will know the answer. With 7 ports populated, the pci-e speed would probably drop to x4 and some at x1. now how much of a speed hit is that for VRAY RT, or is pcie speed only relevant when using SLI?

Thanks again. Exciting times for some DIY action

[Dariusz Makowski (Dadal)]

If u want full 16x pcie speed u need to look at EVGA- they got some interesting rigs that can run multiple x16 pcie. Also make sure ur motherboard can handle the GPU limit. I think u can push 6gpus, at 7+u lose performance or so... its down to GPU per mobo not card per mobo...

[IVOR_IP]

What are some boards that can do 7 pcie @ x16?

http://www.supermicro.com/GPU/GPU.cfm#4U_GPU

[Delineate]

Hey guys so I ordered 3 x GTX 680's but now I came across this and I'm a little worried. Vlado can you confirm any of this??

"Dont go with a 680 just yet.
Vray doesnt use CUDA, it uses OpenCL. Previous NVidias were good enough for OpenCL rendering but the 680 seems to have extremly low direct compute scores. Looks like they want to create a distinction between the GTX and quadro cards.
If you need Open CL for VRay rt go with AMD, they're the best at the moment for any OpenCL work. If you want CUDA for iRay then NVidia is your only option."

This is worrying news if true

[Dariusz Makowski (Dadal)]

Mao u got me worry too ! Any news on it ?

[Delineate]

http://www.anandtech.com/show/5699/n...-680-review/17

man if this is true I might need to exchange the 680's for 580/590's ( and hope they don't catch fire)

or the 7970's even! oh boy, radeon scares me.
any advice would be most helpful

[Dariusz Makowski (Dadal)]

Dont buy wait for chaosgroup official info.

[Delineate]

That's the problem DADAL, I'm put a deposit down for 3 GTX680's, which I'm meant to pick up in two days. I could still switch to the older cards so would be great to get some news before then so I can make a call.
Bah, I bet the next set of Keplers on the 110 chip will render fine. Bad timing I guess. Got too excited.

[Delineate]

Does VRAY RT work on the 7970?

Also check out the scores http://techreport.com/articles.x/22653/7



Really hoping its a driver issue.

[Morne]

Hmmm maybe I was a bit quick to dismiss my GPU of choice for the past few years: ATI?

[Dariusz Makowski (Dadal)]

U cant render on ATI...

[Morne]

I have an ATI 6990, and it renders just fine

[Dariusz Makowski (Dadal)]

ooo so it works on GPU rendering? Last time I check RT GPU on ATI it has either 20min render or crash.

U sure u using GPU or its just vray changing it to CPU once it see it cant use GPU ?

Did u check if ur GPU runs 100% when u RT GPU ?