oh OK, apologies for a BAD comment, it is though compatible (the Duron)
ok, hee is the myth, its generally seen that AMD works well with nVidia and intel with ATi.
also, image quality of nvidia is good rather than ATi's
and speed of ATi is good rather than nvidia's
this above is taken generally, not on every application).
now you decide what to go for, as if i've to say, AMD and nVidia came with something new this time, so go for that combination. ALSO, Apple macs use nvidia in their high-end power macs. thus means nvidia is something to think about.