Thanks Cluberti, but that doesn't seem to work! The description for the two WINNT.SIF settings are as follows; DefaultStartPanelOff = Yes This tells Windows XP to use the Classic Start Menu, and displays the My Computer, My Documents icons as well as others on the Windows Desktop. If set to No, then the default Windows XP Start Menu is used. DefaultThemesOff = Yes This tells Windows XP to use the Classic Theme. Note: This option overrides CustomDefaultThemeFile option when set to Yes. Are you sure they should result in the best performance setting within visual effects? The strange thing is when XP loaded the effects were stiil active, so I went to the visual effects tab in system and as I sat there wondering why all the boxes were ticked, they suddenly all unticked themselves!!! although I still had to press apply before the effects were actually deactivated. In nlite I have ticked to deactivate all of these settings but with no joy, which is strange as all the other tweaks I have done in nlite have worked. The registrytweakage programme Clavicle linked to doesn't appear to contain these visual effect tweaks. Can anyone guess what might be going wrong?