I have a problem with being able to do anything else in the viewport, when using the VFB (edit: VFB2). I have a threadripper 32-core 2990WX on a windows 11 PC with 64GB RAM and a RTX 3080ti, running C4D 2025.2.1 and Corona 13. I have tried changing the # of threads override to -16, -32, -64 and I see a reduction in CPU utilization accordingly, but really no change in viewport responsiveness. I can not even navigate the view of a simple scene with only a single object. Trying to stop the VFB is also very slow. Basically any kind of interaction is impossible. I don’t understand why this is, and I’m wondering if there are any other factors involved, and what can I do about it? Perhaps it’s something specific to the 2990WX?.. I do not have the same problem on my other PC, an intel cpu with much fewer cores. open to suggestions, as this is very frustrating for me, having just switched over to this machine.
There were similar posts in the past. Here are some ideas:
- Make sure you are not using any overclocking
- Make sure your RAM is installed according to the motherboard manual (like AABB or ABAB order)
- Try disabling hyperthreading in BIOS and see if it changes anything
- Check these advice by Juraj - https://forum.corona-renderer.com/ threadripper 2990wx lags while using Interactive rendering in corona #msg159991
Also, in theory this shouldn’t be a problem, but this CPU is now almost 7 years old.
Thanks Maru - I will investigate the suggestions by Juraj. Unfortunately I’m stuck with this machine for this deadline, and perhaps longer term as well 
Hey, mate.
am also stuck to x399 platform for now.
Currently with 2950x
Was considering to get a 500 bucks 2990wx.
Have you solved this issue?
Don’t remember having issues with past 1950x I had.
Hey, mate.
am also stuck to x399 platform for now.
Currently with 2950x
Was considering to get a 500 bucks 2990wx.
Have you solved this issue?
Don’t remember having issues with past 1950x I had.