This is only sort of related, but the subject reminded me:

I use a USB keyboard.

On my laptop, if I hit return VERY quickly when the boot loader is getting
started, it works.  If I miss that window, there's nothing I can do; the
boot loader ignores my USB keyboard.

On another machine I have, the USB keyboard stays working straight through.

With Windows 98, Windows XP, and SuSE linux, the keyboard always works during
boot loader stuff and other system boot-time activities.

Is this a BIOS thing, a boot loader thing, both, or what?

-s