GeFORCE3 3.8ns 64MB DDR ........Best but expensive

GeFORCE2 GTS/PRO 5ns 32MB/64MB DDR Good and Affordable price

GeFORCE2 MX-400 5ns or above SDRAM(M.CLK must be over 200MHz) Acceptable performance and cheap
P.S. But never choose DDR SDRAM coz MX-400 support 128-bits SDR and 64-bits DDR only.

GeFORCE2 MX-200 32/64MB DDR is better solution for MX-200.