After a new installation of Windows 7, the computer's display may be turned off even if the Power Option setting is set to Never.
This problem may occur when the following conditions are true:
This is the first start of Windows after you install Windows 7.
The WinSAT score has not been determined.
Windows continues to count idle time regardless of the active power plan. After 15 minutes of idle time, WinSAT is activated as part of an idle scheduled task. WinSAT changes the active power plan to High Performance. This has a display idle time out of 15 minutes. Because the High Performance plan is activated and 15 minutes of idle time has expired, the display turns off.
Because this is a one-time occurrence from the WinSAT score calculation, you must reset the Turn off the display option. To do this, follow these steps:
Click Start, and then click Control Panel.
Click Hardware and Sound, and then click Power Options.
In the left pane, click Choose when to turn off the display.
In the Edit Plan Settings window, change the Turn off the display option to Never.