Understood.

1. Restart
2. Continue to press DEL key until the Bios comes up.
3. If it's the BIOS I'm thinking of... On the left-hand side, look for a section called Video / Graphics
4. There should be a setting somewhere for Optimus.

5. Uncheck it.
6. Save BIOS settings (varies per computer, on mine it is F10, on yours, you may have to scroll to the bottom and choose Save Changes and Exit.