Dell Latitude C540 - Manual (Page 43)

computer is connected to an electrical outlet.
To change additional Intel SpeedStep options:
Click the Advanced button and then click one of the following options:
Disable Intel SpeedStep technology control
Remove flag icon (from the notification area)
Disable audio notification when performance changes
1.
Click OK to accept any changes, and then click OK to close the Intel SpeedStep window. 2.
You can also change the Intel SpeedStep settings by right-clicking the flag icon in the notification area.