optimize for duron?

[Glenn Sommer]

Within a few days I will receive an old Duron machine.
I was woundering how I should optimize my programs for that machine.
I have been reading in the GCC manual (3.2.3) and I do not find any
informations about optimizing to AMD Duron (here talking about
the -march and/or -mcpu flag). I find flags like -march=athlon and
other stuff like that. But nothing like -march=duron.

What should I then use for my builds ? -march=athlon, -march=k6
or maybe -march=athlon-tbird ?
Is the Duron CPU maybe quite the same as an Athlon CPU ?

From
Glenn Sommer