I'm running Mandrake 9.0 right now.  The first release canidate is already out.  I'm not on a Anthlon so I can't answer that question, but overall, its a great improvement from my last system, Mandrake 8.1.  The biggest improvement is its foreign language support, which gave numerous headaches in 8.1, not runs much much better than M$.  The only real problem I am having with it is telnet, which dosn't run at all.  A turely satisfying OS.
V