Maybe this has been asked before, but I'd like somebody to explain the difference between I686 and P4. One of my computer is an Athlon and the other is a P4. What version do you recommend me to compile? Does any of the 3 possibilities only work in a specific processor or do they all work in all cpus? Is there any speed gain. Up to know I'm always compiling i686 and it works the same in my athlon with XP and in my p4 with W98. Any drawback if I use P4 instead?