Why can't I set my cpu type in kernel config ?

[Jason Usher]

I am installing 8.3-RELEASE on an old 900mhz pentium laptop ... it's an i686 CPU.

By default, GENERIC has "HAMMER" as the cpu, and that isn't working.  So I tried both:

cpu     I586_CPU

and:

cpu     I686_CPU

(I also tried them both lowercase, like i686_cpu)

But all of these fail:

GENERIC: unknown option "I586_CPU"

How can I set 586/686 (you're supposed to set both) in my kernel conf ?

Thanks.