You can control how long the wait is before your screensaver appears on a Windows PC, or switch the screensaver off altogether.
To open the screensaver control box, click the Windows Start button. In the search box, type screensaver and the screensaver box will appear.
You can change the length of time before it appears by using the adjust arrows next to the Wait box to increase or decrease the minutes.
Setting the picture to None stops it from appearing at all.