Buying a GPU for 3D rendering, recommendations?

[markthema3]

Much to my displeasure, it seems that I cannot have my litecoin miner and my rendering on the same brand of GPU, as AMD seems miles ahead for mining but unworkable and broken for rendering. As such, I'm looking to buy an nVidia GPU for my 3d rendering tasks. I'm looking at either a GTX 580 or a GTX 780. These may seem like odd cards to compare, but the 580 is actually quicker than any 600 series single GPU card, and only a hair behind the 780 Ti (see here). I'm wondering if Compute Capability 3.x has the potential to provide better future-proofing in terms of rendering features (say, subsurface scattering). Currently I am not aware of any features available in Blender's Cycles renderer on 3.x cards that aren't available on 2.x cards, but I'm wondering how much potential future development of the render kernel I might be missing out on. If I were to invest in a commercial modeling or rendering package, would I be missing out on features in other packages (I would most likely be looking into MODO or C4D)?

I guess a tl;dr of my question would be this: Is Compute Capability 3.x taken advantage of in any commercial 3D packages?

 

[moonbogg]

I would decide on a software package and then go to a forum specific to that software or go to the software's website for hardware info. I use an Nvidia Quadro for Solidworks, but it sounds like you are doing something different. In my case, the GPU doesn't render anything. The CPU does rendering if I need to make a render image. The GPU processes the graphics on screen with approved driver support, but that's it.

 

[Zodiark1593]

What sort of memory requirements do your projects need?

To the post above, there is some 3D rendering engines that use CUDA to greatly accelerate said rendering. Case in point, the Cycles engine in Blender.

 

[markthema3]

I know Cycles, VRay, Mental Ray, iray, Indigo, LuxRender, pretty much everything I'm looking at support GPU ray tracing and rendering. I'm having a hard time finding information on features of these GPU raytracers and what features are supported on which Compute models.

What sort of memory requirements do your projects need?

Currently not very much, most of my models are rather simple, the complexity is mostly in my materials. However, I'd like to eventually model more complex things, though I doubt I'll be north of of 100k verts. 1.5GB should be plenty of VRAM for the foreseeable future.

 

[Jodell88]

I have experience with Cycles and Luxrender (3D is a hobby of mine). Cycles is only good with CUDA, even though there is an OpenCL backend it is not comparable with the CUDA backend.

Luxrender is OpenCL only and AMD cards demolishes its Nvidia counterparts. A 7870 matches the performance of a Titan.

In the end, choose what rendering engine you want to use and choose your hardware around it.

 

[markthema3]

It seems that most commercial renderers prefer cuda, and I haven't seen any benchmarks for LuxRender. I was under the impression that AMD's compiler had issues with large kernels. OpenCL currently works on nVidia cards in Cycles, but they still don't have working AMD GPU support thanks to the compiler. This might be a cycles only issue though.

 

[Zodiark1593]

I know Cycles, VRay, Mental Ray, iray, Indigo, LuxRender, pretty much everything I'm looking at support GPU ray tracing and rendering. I'm having a hard time finding information on features of these GPU raytracers and what features are supported on which Compute models.



Currently not very much, most of my models are rather simple, the complexity is mostly in my materials. However, I'd like to eventually model more complex things, though I doubt I'll be north of of 100k verts. 1.5GB should be plenty of VRAM for the foreseeable future.

If the compute power is comparable, and scene complexity is low, I'm leaning toward the GTX 580 3 GB if you can find one for less than half the cost of a GTX 780. Otherwise, I'd go the 780 route. This day and age though, I'd stay away from anything under 2-3 GB for rendering. Even if it's seldom, adding displacement and things of that nature will chomp down your RAM.

 

[Imouto]

You can find some GTX 580s 3GB in eBay for $250 or so. Bought mine there. Also, VRAM is spent in complex node setups, I'd say even more than a higher poly count. For example I have a PC mouse design with a 100k poly count that barely pulls 600 MB and a car design with 200k poly count that pulls just 700 MB.

For Cycles a second hand GTX 580 3 GB is just untouchable perf/$ wise. If you're going to use Cycles the CUDA version doesn't matter that much. You'll be fine while you get used to Cycles with 3 GB, really.

As for Luxrender I think they're always a few steps behind Cycles in about everything and it is way harder to learn. That said results always seemed better with Luxrender but that's not the case anymore with Cycles implementing some missing options lately.

 

[Kosmic1]

580s are pretty awesome cards. There is one available with a waterblock for $200 on another forum. I'm not sure if it's a TOS violation to mention it here, but PM me and I'll let you know.

 

[Imouto]

Anyway ppl at blenderartists.org will answer to this way better than any of us.