Ways to enter BIOS for different laptop brand

Del during boot AMI, Award
Esc or F1 during boot Toshiba
F2 during boot NEC, HP OmniBooks, Dell including Latitude, Optiplex, and
Dimension.
F1, F2, CTRL+ALT+ESC Acer
F10 when square in top RH corner of screen Compaq
Reset twice Some Dells
For unfamiliar systems, try F1,F2,F10,F12,ESC or DELETE. Normally the screen will show the instruction on how to enter BIOS, for example, "Press F1 to Enter Setup".