I have a Gateway Desktop P III 866 MhZ system with amibios. I can't get into BIOS setup utility. Docs say hit F1 during setup, but nothing happens. At POST I get a gateway logo page with the note to press tab for systyem messages, I do so and then see the boot messages to a stop point at which time I am instructed to hit esc key to complete, then it goes into the XP boot-up completion. How can I get into the BIOS??