Obviously, a faster processor and more memory help with Poser.  Poser before v7 doesn't know what multiprocessors are, so having dual Xeons or quad-core make no difference to the speed.  But even then, Poser 6- have the single-processor, 2GB-addressing limits of 32-bit archaic applications.  Now that 64-bit and  multiprocessors are becoming more ubiquitous (and e-frontier sees this), we should see some improvements in Poser's handling and speed.

As far as I know, there is no processor capable of near 4GHz yet (3.06 or so at last cough).  It is unlikely that single processors will go much further because of manufacturing limitations versus cost for the granularity of such cpu construction.

In a word, the old Posers have hit their limits.  If you expect to use older versions of Poser with even faster systems - this ain't gonna happen.  The drive is for 64-bit and more processors (which is faster in different ways).   e-frontier realizes this and is making headway in that direction (thankfully!).

Quote - As far as I know, there is no processor capable of near 4GHz yet (3.06 or so at last cough).  It is unlikely that single processors will go much further because of manufacturing limitations versus cost for the granularity of such cpu construction.

By overclocking you may be able to go above 4GHz depending most of all upon what type of processor you are using. "Core 2" processors are known to be able to reach 4GHz with the right cooling.

Here's a quad core processor (Kentsfield QX6700) running at 4.4GHz for instance:
http://www.xtremesystems.org/forums/showthread.php?t=121970
Note the Cinebench score of 2333.

Here's a comparison between single-core, dual-core and quad-core processors running in Cinema 4D:
The Pentium Extreme Edition is the only single-core processor here.

My E6400 gets about 1000 points here.

Right.  But note that Cinema 4D utilizes the multi-processors in rendering - which shows in the Cinebench results.  Poser 6 and earlier don't utilize them - only one processor.  I agree that overclocking can push the single-processor processing to near or slightly above 4GHz, but the multi-core advantage will not help these earlier versions of Poser.

The limitations of single processor processing speeds are becoming to difficult to overcome.  This is why the industry is veering away from that as the cost of manufacturing faster processors is being outweighed by the small speed increases (the inverse of Moore's Law it seems).  Note that multi-core processors are slower than single processors - all of the advantage is in multi-processing (and some clever wiring, as it were, to boost the apparent processing speed - larger caches, shorter connections, faster buses and memory refreshes).