Old AMD system upgrade ?

[bytes2]

I have a old AMD system
cpu - t'bread B xp2000+ @ 2100MHz SocA - mboard kt880.

I want to upgrade the cpu to max possible (with air overclock),
don't want to change MB yet.

Anyone suggest what cpu I should get and If its possible to get it.

Thanks

 

[bytes2]

I believe I am cpu limited with a 7600GT-AGP grpahics card?.
So to get most out of the graphics card I though upgrade cpu.

Would I get much improvement say from xp2800+ to xp3200+/3400+.
Is it worth it ?.

 

[bytes2]

I don't believe I will need any other component upgrading.
I can run >210fsb and have ddr400 memory.