Your Windows 7-based operating system contains numerous settings to optimize your computer's performance and energy consumption levels. Sleep mode lets users specify the time a computer remains active before it shuts down all system resources. Such an option helps save your laptop's energy and cools down its internal hardware. Setting up sleep mode is done using your computer's main power settings.
Open the "Start" menu and then "Control Panel."
Click "Power options" if the view is set to "Large" or "Small" icons. If viewing items in "Category" mode, click "System and Security" followed by "Power Options." You may change the Control Panel's layout by clicking "View By" from the upper-right corner of the screen.
Click "Change Plan Settings" for the type of option you are currently using -- Balance, Power Saver or High Performance. Click the "Change Advanced Power Settings" option.
Expand the "Sleep" option and then the "Sleep After" entry. Click "Setting" and set the time before your computer goes to sleep, in minutes. Alternatively, use the up and down arrows provided to increase or decrease the time set for sleep mode.
Click "OK" to apply and save your power options changes.