this idea appears pretty regularly:
But Iām not sure if Blender devs are really reading the suggestions on rightclickselect.
However, maybe itās in a none destructive way possible via āscaleā?
But maybe thatās something which would fit more into the scope of k-cycles or e-cycles.
I think the devs are aware of right click select, but Iām guessing they only know about the top 10 or so requests.
To be honest I donāt even need to use the simplify options anymore. Since they introduced out of core rendering, Iāve been able to use any size texture because it can load in and out textures on the fly now during rendering. If youāre using very large HDRIās (8k upwards) then you can massively reduce VRAM usage by setting the importance map to a lower resolution. I have a video about it here actually:
That video was pretty intresting, but sadly I rarly use HDRIs.
I prefer procedurally geneerated skies like with PSA.
And that little trick will not help in my case.
Iām currently working on my asset libraries and Iām unsure if should create 4k oder 6k/8k images.
6k/8k will be in most cases much to high, but it would pretty nice if could have everything in a very high res and just scale it down to 4k oder 2k, as I need it.
ah, I just checked that out of core memory thing you mentioned.
I remember, thatās that feature that you can use the RAM, if you are out of VRAM.
But sadly, thatās only working with CUDA ā no OPTIX support 
Are you sure? One of the devs mentioned it works with OPTIX now too when I asked a while back.
pretty sure. Iāve 2x 2080ti with SLI and 64GB RAM.
I can distriubte up to 17GB in my VRAM, before I get out of memory. Thereās no fall back to RAM.
I see the price has been increased on gumroad. What is the reason?
Why are you denoising color passes?
hmm, I wonder if itās caused by SLI. Iām sure it was Brecht who said it worked with Optix now. Iāll have to ask next time Iām on blender chat.
So I can dedicate more time to new features, and to cover additional marketing costs.
that would be nice if you ask him. It would be also nice if you could ask him, if it would be possible to implement the simplify per material/object feature. Apart from that edge case I meanted before, it should be a pretty low hangig fruite, after itās already there 
itās an intermittent necessity based on some of the techniques I employ under the hood.
Hi, I got confirmation that out of core works in Optix mode:
The OptiX backend is using CUDA for memory management, so this works the same between the two and should work. Exception being that acceleration structures have to stay in GPU memory, so scenes that have extreme amounts of geometry wonāt benefit.
I just realised your issue actually as I was typing. Youāre only getting 17gb ram available because Windows steals around 2-3 GB per graphics card. Itās super annoying. Although this doesnāt answer why you would get the āout of memoryā error instead of going out of core after 17GB. Perhaps your system ram is depleted or your scenes have masses of geometry (try instancing if possible, proper instancing though, not shift D).
okay, intresting.
is this out of core thing only working for materials?
because the test scene I used for testing this, are just some Szuannes, with a pretty high render subdivision (but very low subdivision for the viewport).
there are no textures in that scene. The 17GB are only mesh.
Have you also asked for the simpilfy per material?
Yes the geometry BVH remains in VRAM only, so thatās probably your issue. Must be a lot of suzannes! Are you instancing them?
There are several types of instancing. Not all of them reduce memory consumption. I have a short 2ish hour course which goes into great detail regarding the different instancing types and the various ways to set them up:
ahhh good to know. I did this test scene only for testing out the limits of Blender.
Thatās why I didnāt instanced them.
So, I will do maybe tomorrow a test scene to bring blender with some 8k textures to the limit and than I will see if this out of core thing is working.
So I guess you didnāt asked him for the simplify per material feature?
Iām able to successfully viewport render I think it was several million subidivided Suzannes in the tutorial. Not bad as Iām still on a gtx 1070! 
Oh sorry, no I didnāt ask about the simplify thing. I donāt like to mention feature request on there as itās strictly for development issues.
Iād recommend asking on the blender today weekly feature video. They do questions at the end, so you could direct him to the request on right click select and heāll check it out live during the video. Might help drum up a bit of support for it.