24-core Theradripper 3960x or a GPU-based workstation with RTX 2080 Ti's?

[Alex_M]

So the new Threadrippers are right around the corner and I'm contemplating upgrading my current workstation. What do you think would be a better choice for rendering in Vray? The 24-core Theradripper 3960x or one (or two) RTX 2080 Ti's? Pros and cons? The last time I've been experimenting with GPU rendering was a bit over a year ago and my overall impressions were not that great. There were important features that were still not supported and I've also been experiencing some strange behaviors/bugs. Is this still the case? CPU rendering has been rock-solid for 99% of the time. Any reasons to go with GPU rendering this time?

[Neilg]

What kind of work do you do?

If you regularly go north of 64gb and hit up to 128gb ram, go with cpu.
If you do product, ad or studio based renderings i'd go gpu.

[Alex_M]

80% arch-vis (of which 70% exterior and 30% interior). The remaining 20% is product-vis. So far I've never exceeded the 32 GB of RAM on any project. Normally my RAM usage during heavier exterior renderings hovers around 10-12 GB, maybe 15 GB in some extreme cases.

[oglu]

I would add two headless 2080Ti with NVLink . Use them only for renderig without a monitor.
And your 1080 Ti is doint the viewport work.

[Alex_M]

How fast is a 2080 Ti at rendering using RTX (Vray Next Update 3)? Are there any benchmarks that I can see comparing it to a CPU such as Threadripper 1950x/2950x?

[squintnic]

Watch out for being able to use 2080Ti with NVLink in current GPU version and Nvidia drivers.

[oglu]

How fast is a 2080 Ti at rendering using RTX (Vray Next Update 3)? Are there any benchmarks that I can see comparing it to a CPU such as Threadripper 1950x/2950x?

Comparing CPU against RTX isnt easy. And it does deliver diffrent results on diffrent scenens.
Depends on how much geo and how mutch shading work has to be done.

CPU could be faster on some and on some RTX will be faster. Depends also on how much hardware you throw at it.
Its much asier to upgrade GPUs.

I fear you have todo your own testing.

https://www.chaosgroup.com/blog/prof...idia-rtx-cards
https://www.chaosgroup.com/blog/v-ra...for-nvidia-rtx

[Alex_M]

Are there still "asterisks" with GPU rendering? Like unsupported features, textures, shaders etc? Also, how am I supposed to make a decision when the Vray benchmark renders two different scenes with CPU and GPU? Am I supposed to blow a few thousand $ on new hardware and test all of this for myself?

[francomanko]

i also find it a bit bizarre that the scenes are different, Gpu and Cpu cant be that different.

[Ihno]

GPU doesn't support all features (yet). Most important ones are there, though.
Not only vray features are missing. Other plugins might also not render as expected.

GPU's can be impressively fast on many scenes especially now with rtx support.

You're mainly rendering stills right? So rendertime isn't that much of a problem probably.
Well, at least not the "I gotta get 2000 of those images rendered within a week" kind of problem.
Getting stuff to work well on the gpu (i.e workaround missing features / fitting the scene in the vram) can take some hours.

For me (who does 100% animation) it makes total sense to put this effort in if I can render 200-300% faster afterwards.
But if I'd do only stills I probably wouldn't care.

You decide between stability and being able to throw anything at your scene vray has to offer.
And much faster rendering but less stability and fewer features.

[glorybound]

The AMD three 64-core, 128-thread CPUs are supposed to trickle down to the consumer in 2020. It is a CPU vs GPU race.

[francomanko]

GPU doesn't support all features (yet).

Thats been the status for how long now? Not supported in 3.6, not supported in next....will they ever be supported