I really don't have a problem with any of my other 3D applications, in fact I rendered a 4000 x 2500 px picture in Poser on the highest quality settings in about 10 minutes.  That would have taken all evening or all night with my old system.

I used to have a memory optimization program, but I hadn't really seen any increase in performance so I uninstalled it.  That was some time ago.  I also had System Mechanic which was supposed to cure memory leaks and deframent the ram.  

I may try to up my ram, it is an XP 32 bit system.  I've read that you can activate the 3 gigabyte switch in XP and make it accept that much--I also understand that it can't use more than 3 gigs or handware drivers would start having issues.