I upgraded my gerforce 4 mx 420 64 mb to a nvidia geforce fx 5200 256mb and here are my results:
3d Mark 2001 : old card MX420 - Score:1,182 , new card FX5200 - Score:2,218
System Works 2004 Performance Test: old card MX420 - Score:131.1/306.0 , new card FX5200 - Score:165.5/327.1
As you can see there was a pretty big performance increase. This is for those who didnt think the FX5200 would give you a big noticable performance inhansment over the MX420.
That is a pretty big performance increase in 3d mark isn't it?