slowness on downtown lots

[waynefox]

i have DD and all EP and SP

AMD dual core 3.0Ghz (with the amd patch)
2 GB RAM
Nvidia 9800GT 1GB card (updated drivers)
600w power supply

ok to the problem
the game runs great exept for downtown lots which are slowed down and a  jerky (it start out ok but the more sims that show up, around 8 for a tot. of 10 to 12 sims the worst it gets)
is there any way to fix this other than buying a new video card
(i have the Visitor Controller with ban critters and whitches)

[FourCats]

I don't think buying another video card would help. Maybe reduce how many sims are allowed on a lot using the user.startup.cheat?