If you're not getting even 1000 in 2003, I doubt you'll get 15000 in 2001... to get 15,000 in 2001... you're gonna need probably an ATI 9700 or a GeForce4 Ti4600 overclocked... not to mention one helluva processor... such as a P4 2.5 or higher, or an Athlon XP above 2 Ghz.
Duh... just read the origional post... you probably have the CPU power to do it... but you're not gonna hit 15,000 with a Ti4200. Not to mention your PC2100 RAM holding you back... you might hit 15,000 if you set all the settings as low as they can go.