Lenovo G580 User Guide - Page 34

Chapter 2. Learning the basics „ Using passwords Using passwords helps prevent your computer from being used by others. Once you set a password and enable it, a prompt appears on the screen each time you power on the computer. Enter your password at the prompt. The computer cannot be used unless you enter the correct password. Note: This password can be from one to seven alphanumeric characters in any combination. For details about how to set the password, see the Help to the right of the screen in the BIOS setup utility. Note: To enter BIOS setup utility, press F2 when the Lenovo logo appears on the screen while the computer is starting up. About NVIDIA® OptimusTM (on select models Optimus is a GPU switching mechanism which automatically switches the active GPU to perform image-rendering tasks. If no graphics-intensive programs are running, the integrated GPU will be selected as the active GPU to preserve battery life; if you start high-definition movie playback or a 3D game, the image-rendering task is automatically switched by Optimus to the discrete GPU to produce high graphics performance. When Optimus is enabled, switching between integrated and discrete GPUs is performed automatically without user intervention. 30