which kernel for athlonXP-official answer needed

[bailout_ubuntu at yahoo.co.uk]

I am trying to get an official definitive answer as to which kernel is best 
for AthlonXP chips- the k7 or 686? I have searched the ubuntu forums and read 
the unofficial guide etc and the results are confusing. The guide indicates 
686, the description with the debs in reps don't mention the athlonXP 
specifically but would seem to suggest k7 and advice on the forum is 
contradictory with some saying k7 and some saying 686. There is obviously 
confusion on the issue and it would be nice to be able to answer it 
conclusively, ideally by getting a response from the developers who compile 
the kernels.

I have posted a topic on the forums about it and several other people have 
expressed an interest in getting the answer as well.

The main reason I have doubts over the k7 kernel is that I can remember that 
k7 was the pre-release code-name for the original athlon. Since then the 
athlon architecture has undergone further development including the addition 
of some intel routines, ie sse. Hence my wondering whether the k7 kernel was 
for original athlons and whether the 686 would be better.

From the split on the forums btw the two it is obvious that both work :D but 
it would be nice to know which was the best.

my thread on the forum is here 
http://www.ubuntuforums.org/showthread.php?t=22218

Perhaps the descriptions on the kernels could be updated to specifically 
mention athlonXP chips to avoid any confusion in the future?

thanks