kernel optimization

I have read in linuxJournal that I can be able to optimize my kernel using this parameters: CFLAGS='-o9 -funroll-loops -ffast-math -malign-double -mcpu=pentiumpro -march=pentiumpro -fomit-frame-pointer -fno-exceptions' I have some problems 1. My cpu is a Atlon at 900 mhz, not a pentium. With what to replace pentiumpro ? 2. I have compiled at home the kernel ignoring -mcpu and -march, the kernel was compiled fine, with no errors, but after i have installed, it does nothing. It is broken !, so how to optimize my kernel ?