My old laptop had 512 of RAM and a 1.8 gig processor.  When I was using it with Poser 6 I had a horrible time with many images.  By images I am talking single figure with clothing, hair, skin texture.  My renders would take anywhere from 20 minutes to an hour, sometimes more.  I usually had to use a bucket size of 32 or less.

And if I was actually making a scene with other things in it other than a single figure, I had to render in pieces and assemble in post work.

I now have a different computer with 2 gigs of ram and I use Poser 6. Single figures render pretty fast, depending on textures and ratracing and shadows of course.  Complete scenes have given me grief and I have to resize the textures, lower the bucket size and sometimes render in pieces. But for the most part 2 gigs is working well for me.

512 was "workable", but could be very frustrating at times.  I strongly recommend that you learn Poser 6 lighting and IBL so that your computer doesn't have to worry about trying to render a gazillion shadow maps for 30 lights. That will make rendering so much faster for you.

"It is good to see ourselves as others see us. Try as we may, we are never
able to know ourselves fully as we are, especially the evil side of us.
This we can do only if we are not angry with our critics but will take in good
heart whatever they might have to say." - Ghandi