Keyshot 9/10 Gpu Suggestions

[tim.bradley]

Hi

Im currently looking at upgrading our main work machine and just wanted to ask some advise.

We use my machine 60/40 Solidworks/Keyshot, and mostly network rendering to offload final renders/animations to run over night.

However we have an opportunity to upgrade, the CPU we will most likely go for one of the recent threadrippers, but we are trying to find out the best spec GPU to go for.  As we still do more work in Solidworks, a quadro card is needed for compatibility (even though I know gaming cards work, we need to have the best stability and also support from our resupplier)

However, rather than opt for a high end RTX 5000, I was thinking if we could save money by going for a lower spec quadro as the main display card, then possible a RTX 3080 as a secondary card for Keyshot.  Would keyshot be able to utilise the RTX 3080 if it is setup as a secondary card, or would it have to be the primary card to work?

Cheers

[DriesV]

Hi Tim,

Yes, you can mix and match NVIDIA GPUs, and use any or all for rendering in KeyShot.
Luxion's recommendation is to get a card with RTX technology for hardware raytracing acceleration.
As for the specific GPU, then RTX 3080 will be very fast (faster than dual RTX 5000). However, RTX 3080 has "only" 10 GB of memory, with no way of expanding it through NVLink (unlike RTX 5000 and other Turing cards). So depending on the kind of scenes you render, this may become critical. For this reason alone, I would personally not recommend getting an RTX 3080 for production work in KeyShot. The RTX 3090, while more expensive, is a much safer option, as it has 24 GB of memory with NVLink as an option to double that, if you get a second card.

Dries

[mafrieger]

...
However, RTX 3080 has "only" 10 GB of memory, with no way of expanding it through NVLink (unlike RTX 5000 and other Turing cards). ...
The RTX 3090, while more expensive, is a much safer option, as it has 24 GB of memory with NVLink as an option to double that, if you get a second card.

Dries

@DriesV
yes this would be my first guess too.

But: Do I really need the NVLink (Bridge Hardware) to make it work in Keyshot?
For other renders based on Nividia's Optix I saw benchmarks of 3x 3900 RTX cards with great results (nearly 300% speed)
In theory this shouldn't work because 3090RTX only support NVLink for 2 cards.
But it seems to work - without the possibility to connect 3 cards with NVLink hardware bridges.

If this works:
1) ->is this also possible with KS10?
2) -> shouldn't it be possible to make 2 3080RTX work - without NV-Link bridge but with far more power than 1x 3090 (about 170%) and with nearly the same memory size (2x10GB=20GB vs 1x24GB) ??
This would be an awesome solution!
3) -> if THIS is possible: where would be the border from Keyshots side (GUI setup possibilities)?
Is it possible to setup 4x RTX cards with GUI? Or 3 RTX cards plus one small Quadro for graphics?

[DriesV]

3 times RTX 3080 will be (almost) 3 times faster than a single RTX 3080. But you are still bound to the same memory limitations as of a single card, in this case being 10 GB.
This is where NVLink comes in, where you can pool the memory of two cards, effectively doubling the available memory (with some performance caveats). You don't need NVLink for performance, you need it for the memory pooling. NVLink is possible on previous generation cards like RTX 2080 or even RTX 2070 Super. NVIDIA stripped that functionality for RTX 3080 and positions that card very clearly as a gamer card.
It depends a lot on the scene, but it isn't very hard to push the GPU's memory usage beyond 10 GB.

Dries

[mafrieger]

@DriesV
thanks for fast and detailed response!
With this piece of information: would it be possible to run 4x 3090RTX with 2 pairs of NV-Link coupled cards in KS10 to get the power of 4 cards and the memory of a pair (2x24=48GB) ?
(if using GPUs and MoBo with mechanical fit for 4 Cards)

THIS would be a hell of a machine

[mafrieger]

just have a look at the topic "hell of a machine" myself. Coupling 4 cards to 2 pairs seems to be unintended working - but only in the past. With newer drivers it's not possible anymore (tested only with 20x0RTX cards)
https://www.pugetsystems.com/labs/articles/Unsupported-How-to-Make-Dual-NVLink-Work-on-Windows-10-1688/

[DriesV]

I think you have to consider if you really want to have 4 times RTX 3090 in a single machine.
The power draw for those cards alone will peak at 1400 W. It is going to be somewhat of a furnace. And then there is the physical size/thickness of the card, which means that almost (or absolutely?) no existing motherboard or case will be able to accommodate it.

Dries

[tim.bradley]

Thanks very much for the advise!!
At the moment we only use a P2000, so anything is an upgrade.  What kind of limitations would occur with only 10gb of ram on the 3080?  Would it crash out during a render, or would it slow down?

[mafrieger]

I think you have to consider if you really want to have 4 times RTX 3090 in a single machine.
The power draw for those cards alone will peak at 1400 W. It is going to be somewhat of a furnace. And then there is the physical size/thickness of the card, which means that almost (or absolutely?) no existing motherboard or case will be able to accommodate it.

Dries

of course you have to use the right MoBo and card modell: but it's possible form hardware POV :-D

just choose: Gigabyte RTX3090 Turbo which is only standard 2 Slot Design and a workstation Mobo having the right amount of PCIe 16x slots with the right spacing e.g. Supermicro H12SSL-C

And it's not too hard to find the right power supply - at least when your country is operating at 230V...

But the big question: Does KS10 could make this work? (GUI for setup 4 cards and internal) ??

[DriesV]

... What kind of limitations would occur with only 10gb of ram on the 3080?  Would it crash out during a render, or would it slow down?

KeyShot would throw an error, and you wouldn't be able to use the GPU for rendering. KeyShot as such wouldn't crash. The rendering would fall back to use the CPU instead.

It could very well be that 10 GB is plenty for your scenes and textures. Maybe you can look at the memory consumption of the KeyShot process in Task Manager (on Windows) to get a rough idea of how much memory your scenes are using.
If you don't typically have many large textures on your models, then you can do a lot with 10 GB. It will be able to handle a lot of geometry.

Imho, if the card is to be used in a professional context for production work, I would skip the RTX 3080. I have tested plenty of scenes that go above and beyond 10 GB. 

Dries

[mafrieger]

uups same time post (see above)

[DriesV]

...
But the big question: Does KS10 could make this work? (GUI for setup 4 cards and internal) ??

From our core GPU developer:

Our implementation of NVLink should function with multiple NVLinks in the system, but it is untested.

But like mentionned in the article you linked, it appears recent NVIDIA drivers don't support multiple NVLinks. At least not for GeForce drivers and cards.

Dries

[mafrieger]

beside NV-Link and memory advantages...

when just thinking about raw power of 4x cards and make it accessible as described below (hardware hints):

If KS10 could make this possible
=> this could be
- from technical pov a perfect edge test for setting up an using this power (for gui and interna)
- a speed bump for some daily internal things like dev, testing, debugging, webinars
- a perfect marketing stunt

I think you have to consider if you really want to have 4 times RTX 3090 in a single machine.
The power draw for those cards alone will peak at 1400 W. It is going to be somewhat of a furnace. And then there is the physical size/thickness of the card, which means that almost (or absolutely?) no existing motherboard or case will be able to accommodate it.

Dries

of course you have to use the right MoBo and card modell: but it's possible form hardware POV :-D

just choose: Gigabyte RTX3090 Turbo which is only standard 2 Slot Design and a workstation Mobo having the right amount of PCIe 16x slots with the right spacing e.g. Supermicro H12SSL-C

And it's not too hard to find the right power supply - at least when your country is operating at 230V...

But the big question: Does KS10 could make this work? (GUI for setup 4 cards and internal) ??

[theShopFloor]

I've just installed an RTX 3090 in my workstation for these exact same reasons. I've already had scenes loading in at 21Gb, so a 3080 would have been the wrong choice for me.
A few things to note, the performance is astounding. Mind blowingly astounding. It absolutely wipes the floor with my old 2950x CPU, I'm yet to try it with the incoming 5950X, but I'll comment when it arrives.
For the money, the RTX 3090 was the biggest performance leap I've ever experienced in 15 years of rendering.
I'm watercooling it and grabbing a second in NV-Link for double the rendering performance. Amazing card.

[quantum]

Got the Founder Edition 3090 and wanted to confirm that KeyShot could take advantage of (2) GPUs. Read through the comments and it seemed like it but didn't want to assume before picking up a second card. I did pick up the NVIDIA GeForce RTX NVLINK BRIDGE for 3090 cards so have that and the motherboard I'm using / power supply can accomidate

When you select the GPU render mode with two cards, does KeyShot simply send it to both GPUs to process the data which are linked (i.e. splits the work between the two processors in realtime) or is there additional configuring to do to make it work?

Also second everyone's comments - the 3090 is a remarkable card, thanks all for weighing in!