I found this interesting article on the VMware Knowledge base site, at least one I really never thought of … a virtual machine doesn’t need a screensaver. Below is exactly told how to do this.

  • Screen savers are not necessary for virtual machines
  • Running screen savers wastes CPU resources
  • There is no interface option to disable the screen saver on the log on screen in Windows  
     
    To disable Windows Logon Screen Saver:
    Click Start > Run, type regedit, click OK.
    Locate the following registry key: 
     HKEY_USERS.DEFAULT\Control Panel\Desktop
    _ Double-click the _ScreenSaveActive
    string value item in the Details pane.
    In the Value data box, replace the number 1 with the number 0, and then click OK.

For more information, see Microsoft KB article https://support.microsoft.com/kb/185348.