680s, 780s, Titans

[Andrew Smith]

Would this be Hackintosh, Linux or PC? Just curious as I am thinking of what my own next build will be post-WWDC disappointment.

[Paul King]

Hi Andrew

PC – Win 7.

WWDC disappointment?

Thanks

Paul

[Juan Salvo]

Counting cores is not a good way of measuring performance between GPUs. It’s very much an apple to oranges comparison.

Colorist | Online Editor | Post Super | VFX Artist | BD Author

https://JuanSalvo.com

[Paul King]

Hi Juan

Well this holds true for the 690, however my question was in context of RAM on each card. Peter from Blackmagic has already informally qualified the Titans, but the issue here is we have no info on how many are require for 4k work.

All we have so far is 4 x 680s for 4k.
I’m simply asking how many 780s and how many Titans.
Maybe I’ll be the first guy to find out if no one else knows.
But this has become a significantly important question now that we have new GPUs available in 2013. An expansion chassis has always been a very expensive option and only serves to house what will become redundant technology.

Thanks

Paul

[Joseph Owens]

[Paul King] “An expansion chassis has always been a very expensive option and only serves to house what will become redundant technology.”

My hope is that an expansion chassis is as beneficial as the cards housed in it, and those can be changed as technology evolves. So if two Titans equals 4x690s, then does 4 Titans = 8 690s? I don’t think the math works that way, but 8 GPUs would always be a non-starter for Resolve/Mac no matter what, so the expansion option should remain a viable option for massive processing for some time.

jPo

“I always pass on free advice — its never of any use to me” Oscar Wilde.

[Juan Salvo]

One Titan does not equal one 690… much less two. Roughly speaking 1 Titan = .85 690s. Or 1.40 680s.

But that’s an incomplete evaluation.

Let me just say this. If cost is no object just use Titans. As many as you can. And always use an expansion chassis. Trying to use multiple GPUs (more than 2) on a mother board can be very frustrating.

Colorist | Online Editor | Post Super | VFX Artist | BD Author

https://JuanSalvo.com

[Al Arnold]

I’ve been running 3 GTX 580s + Decklink card in a single Windows 7 system/chasis for a year or so without issue. Running a beefy PSU, and huge case though. Cooling, configuration and noise can definitely be issues, but if addressed much more affordable than an expansion chasis.

[Juan Salvo]

I’ve seen behavior vary from manufacturers to manufacturer, and between card models, and firmware updates. It works for you, thats great. But by and large, there tend to be issues with multigpus directly on the motherboard, where there are few within the expansion chassis. Better all around to just get an expansion chassis.

Colorist | Online Editor | Post Super | VFX Artist | BD Author

https://JuanSalvo.com

[Paul King]

OK

I take it from the responses that not many here have enough experience with this hardware.

Win/Mac limit 4 GPU, so bigger expansion chassis makes no difference.
Titans in the release versions all come from the one factory so no variation between manufacturers for the moment.

I take it you guys are all Mac guys (with the one exception).
The Supermicro board is specified by Davinci for the purpose of multiple GPUs. The notion that GPUs work better in an expansion chassis doesn’t make sense as rhe expansion chassis has less bandwidth than the motherboard.

If there are formulas bandied around such as 1.4 x 680 then the question is relevant comparing CUDA cores. Blackmagic here in Australia have said so to us, they just haven’t released any testing results with the newer GPUs.

It makes no sense to put in as many Titans as possible as they are expensive and there is obviously a limit to the number of CUDA cores required for 4k. My question was how many – 4 x 680 = 6000 cores.

Dont want to seem too ungrateful for the replies but they’re not very helpful for the original question.

Thanks

Paul

[Juan Salvo]

Hi Paul,

[Paul King] “Win/Mac limit 4 GPU, so bigger expansion chassis makes no difference.”

Actually the GPU limit on Macs is 5. I happen to run both Mac and Linux.

[Paul King] “Titans in the release versions all come from the one factory so no variation between manufacturers for the moment.”

Sure but the question and discussion wasn’t just about Titans. And there is also the issue of motherboard manufacturers.

[Paul King] “The Supermicro board is specified by Davinci for the purpose of multiple GPUs.”

Why don’t you take a look at the config guide? They still spec an expansions chassis for anything more than 2 GPUs.

[Paul King] ” The notion that GPUs work better in an expansion chassis doesn’t make sense as rhe expansion chassis has less bandwidth than the motherboard.”

Well “better” can mean a lot of things. I meant it as in more stable and reliable. As in all the cards show up in the os between boots. As far as the issue of shared bandwidth, which has been brought up before, it’s not a factor thanks to clock sharing.

[Paul King] “If there are formulas bandied around such as 1.4 x 680 then the question is relevant comparing CUDA cores. “

No, that’s precisely the wrong comparison. Even NVidia will tell you, the number of cores alone is not a good indicator of performance. My multiplier is based on my own tests with those cards.

[Paul King] “It makes no sense to put in as many Titans as possible as they are expensive and there is obviously a limit to the number of CUDA cores required for 4k. My question was how many – 4 x 680 = 6000 cores.”

You want to talk expensive, spec out a config with K5000s. Actually Titans makes great sense for a bunch of reasons. One is the amount of RAM onboard the card which is a factor today, but will be an even bigger factor tomorrow. Again the number of cores is not what you want to be counting. But go right ahead and do as you like.

Best of luck to you.

Colorist | Online Editor | Post Super | VFX Artist | BD Author

https://JuanSalvo.com