How much RAM do you have? you should have at least 512MB. 1GB would be nice. More RAM would help out a lot with lag.
Also, you might want to turn down some of the graphics options for the game.
Sometimes you can't do anything about the lag. Just way too many people in one spot for your computer to generate, like in Jueno.
If you are getting a new card, get something with at least 128MB RAM on it and at least AGP format. If your computer supports it, PCI-Express would be even better. I haven't been keeping up to date on the video cards but you might want to check out these sites:
graphics.tomshardware.com/graphic/20050524/index.html
graphics.tomshardware.com/graphic/20041222/index.html
graphics.tomshardware.com/graphic/20041004/index.html
why does it keep truncating my link??? just gotta copy and paste...
Edited, Thu May 26 12:35:21 2005 by Kakashisan