During your tests it might be an idea to try a render without Branched Path Tracing, I believe it provides less noise in concentrating on particular areas of a render where noise might be a problem but that is at the cost of much longer render times. I very rarely use it but set the pixel samples to 50 on the basis you can always stop the render at any point you are happy with it. It is a question of finding what works for you as noise, to some degree at least, is subjective and the scene being rendered can have an impact on at what point noise is acceptable.

This was stopped early in the render as this is the sort of scene where sharp crisps edges are not really expected and some noise may well be acceptable.

 

 

I use Poser 13 on Windows 11 - For Scene set up I use a Geekcom A5 -  Ryzen 9 5900HX, with 64 gig ram and 3 TB  storage, mini PC with final rendering done on normal sized desktop using an AMD Ryzen Threadipper 1950X CPU, Corsair Hydro H100i CPU cooler, 3XS EVGA GTX 1080i SC with 11g Ram, 4 X 16gig Corsair DDR4 Ram and a Corsair RM 100 PSU .   The desktop is in a remote location with rendering done via Queue Manager which gives me a clearer desktop and quieter computer room.