Quote - will more memory make a diff?

Yes, if you mean physical memory (the chips on your motherboard) and if you have less than 2 GB of those.
Because more memory means bigger bucket = faster rendering, and anyway Windows gets very slow when having to us the swap file (virtual memory).

Quote - and is that what you mean with RAM?

RAM, "Random Access Memory" is the name of what we call "memory" on a computer.

A computer has 2 types of "memory":

There is RAM, also called physical memory, and the virtual memory, also called Swap or paging file, which is actual memory written temporarily to the disk to free some real memory for some other task.

Since the disk is much, much slower than the actual RAM chips, the Virtual memory is very slow, and you'd better not have to use it. Thus the need to have as much "real" memory as Windows can handle, and that's 2 GB.

BTW, Poser's renderer is slow.  Take a Poser scene, import it into Vue Infinite, and render it: It will take 5-10% of the time Poser itself will take, on the same computer...  :-/