Well with that 450 MHz CPU you just won't be able to use the videocard to it's full potential. You're gonna need a 600+ CPU to maximize its capabilities. For example, when I upgraded my old PIII 500's videocard from a Savage4 to a KYRO II, the difference was only around 5-15fps.

so i need to upgrade my machine 2 a 600+
Should i buy extra ram card?

How much you got right now? I highly recommend getting 256Megs+