So it is basically impossible to use iray with an RTX 3070 or similar?

tcassat

I had an old GTX980 (VRAM=4GB) a long time ago and didn't have many problems (except that renders took forever) but now I've upgraded to an RTX 3070 (VRAM=8GB) and to my surprise it's basically impossible to use it to render images unless using certain tricks.

The problem is that the GPU runs out of VRAM and iray automatically switches to the CPU. This happens even in simple scenes (I am using just a simple asset and three genesis 8.1 models with simple outfits) and this is enough to make the render engine disregard the GPU completely.

The only way for me to render this scene with only 3 models is to close the program and open it again, because this way it apparently stops using VRAM for nothing, but this is not a good solution because it forces me to do the same thing every time I go to render something...

I know it is not possible to work miracles with a GPU of only 8GB, but I'm also surprised that iray does not have any kind of automatic optimization... It's good to remember that even top end-user GPUs like the RTX 3080ti have no more than 12GB, which is no big deal either, which makes almost no GPU for home use really suitable for iray on DAZ Studio, with the exception of the RTX 3090 or NVidia Titan, but it's quite questionable if these GPUs are really for home use and not industrial use...

Can anyone recommend me some plugin or something that optimizes the scenes? I don't think this is possible really since 3 genesis 8.1 models and an asset is already enough to exhaust the VRAM, so I guess there is no way to work miracles, which makes me wonder how people (including me) rendered things back in the day with GPUs with less VRAM...

marble

Well there's this:

https://www.daz3d.com/scene-optimizer

That's what I used to use with my old GTX 1070 but I've since upgraded. I was going to go for a 3060 but my generous family offered to pay the difference between a 3060 and a 3090 which means that I no longer need to use the Scene Optimizer.

Pickle Renderer

I had this problem with a 2070, so I bought a 3060 12GB.  8GB isn't enough for 3 models really.  You can do it if your environment is kind-of spartan.  Another option is composition, to render separately and layer them in GIMP or Photoshop or something.  It's also often the case that you don't need very high detail maps if your shots aren't all close-ups.  There are tools available in the store for reducing map size in the scene, saving your valuable RAM.  Scene Optimizer is one such thing.

kraftwerkd

8gb VRAM won't be enough for 3 G8.1 models with wardrobes and hair unless you use Scene Optimizer to reduce the maps to 2K. Pickles suggestion of compositing the scene might be the best way around as you'll be able to retain the full map resolution while still working within the bounds of your GPU. I got started with Daz on a 6GB 1660ti (12GB 3060 now!) so if you need any tips to make scenes fit, feel free to ask.

PerttiA

tcassat said:

It's good to remember that even top end-user GPUs like the RTX 3080ti have no more than 12GB, which is no big deal either

12GB's in practice is double the 8GB's and makes a huge difference.

When one gets an 8GB card, only about half of it is available for Iray rendering because Windows, DS and the scene, all take some and one needs to have some for the 'working space' that the process uses - On an 8GB card, all that amounts to about half of the VRAM the card has, but when one has an 12GB card, after windows, DS, the scene and working space taking their share, one still has 8GB's left for rendering.

The funny thing is that one of the best cards for DS, is the 3060 12GB that can be bought (new and unused from the stores) at around 400 Eur/USD

winddancer6440

Nvidia controll panel/ applications tabor programs tab, Add Daz Studio.

 

privatepixels99

Just to chime in on this subject with an irrelevant $0.02...

I used an M5000 which is basically a GTX 980 with 8Gb of RAM for years. (Until this week actually. I now have an A4000 courtesy of the kind folks at Ebay.) I regularly rendered scenes of 15+ characters on my M5000 with the judicious use of Scene Optimiser. I imagine that the same techniques I used on the M5000 will work a treat on the 3070.

I found that the heart of the matter is having a good grasp of the implications of the resolution your output needs to be. For example, there's no need to be using 4k surfaces if you're rendering out to a 1920x1080 image, 2k or less will do just fine. Also, as assets get further away from from the camera in your scene, you can reduce the resolution of your surfaces even more without noticable effect in the final render.

 

artxtap

i once bought an 8gb card, VERY disappointed!! it would only 'turn on/ work' when the view port was changed to iray!! it did NOTHING when rendering, like a dead frog on a log!! got a 12gb card, much much better!! it actually turns on / works when rendering imagine that!

Pickle Renderer

It's why I bought a 3060 12GB instead of a 3070 (or indeed the 3060 Ti).  That extra speed is meaningless if the whole thing drops to CPU when you stress it with assets a little.