So you are saying that if you had a computer with a super powerful CPU and a good amount of DRAM that would be all that you need. No need to have a super powerful Graphics card. because Daz3D would render everything only using the CPU?
no, that is not exactly how it works
the video card for IRAY (so it HAS to be nvidia) will increase the speed the image will be rendered. For the video card to be uused, it has to have at least the same amount of memory required to hold all resources.
so lets say your video card has 8 GB and your pc has 16GB RAM. All the maps and geometry of your scene uses 8.5GB of memory
on this case, the video card will not be used because it does not have enough memory. only the ram will be used.
I think that for RTX cards is also different
Iray [VERBOSE] - IRAY:RENDER :: 1.19 IRAY rend stat : Geometry memory consumption: 47.5837 MiB (device 0), 0 B (host)
Iray [VERBOSE] - IRAY:RENDER :: 1.19 IRAY rend stat : Texture memory consumption: 738.486 MiB for 105 bitmaps (device 0)
Iray [VERBOSE] - IRAY:RENDER :: 1.19 IRAY rend stat : Lights memory consumption: 44.582 KiB (device 0)
so if the part in bold is more than Vram you have, it will ignore the video card