When you use a Microsoft Wireless Optical Desktop mouse that uses Microsoft IntelliPoint software on Windows XP Service Pack 2, your screen saver never activates.
This behavior may occur if the DELL PCM service, designed to start media programs faster, and the DVDLauncher service, used for DVD playback, are running in the background.
To workaround this behavior, disable the PCM and DVDLauncher services:
1. Start / Run / MSCONFIG / OK - NOTE: See How do I disable common startup programs, settings, and drivers to troubleshoot issues in Windows XP?
2. Select the Startup tab.
3. Clear the DVDLauncher box and the PCMService box.
3. If the eTray box exists, clear it.
4. Press Apply.
5. Press Close.
6. Shutdown and restart Windows XP.