Speed Up My Project 64 Emulator

my system:
P4 2.4G
516MB
WinXP-Home V
ATI 9000Pro 128MB

just installed Project 64 1.5V
played a few n64 games on it
i noticed that some games play pretty slow> especially racing game

can anyone recommend a good plug-ins or fix to increase the speed of my n64 games

Use ultra64 i run all my roms on that on a 450mhz and they have never jerked. i have about 40 N64 roms now with never a problem

hehe, ultra64 runs fine even on my old system =) (p2 400 with a matrox g200)