How do you access cmos set up on a compaq presario notebook?

To access the CMOS setup on a Compaq Presario notebook, restart the computer and immediately press the F10 key repeatedly as the system boots. This should take you to the BiOS setup utility. If F10 doesn't work, you can also try pressing the Esc key or F2, depending on the specific model. Once in the BiOS, you can navigate using the arrow keys to adjust settings.