GPO to lock workstation after it is idle for X minutes without forcing a specific screensaver

I'm trying to lock XP workstations after a period of inactivity via GPO. From what I can tell, one of the requirements is that a screensaver must be set. It appears that the only way to force the screensaver is to force a specific screensaver. I'd rather just set a default screensaver to use when a different one has not been specifically selected on the client while also removing the ability on the client to opt-out of a screensaver.

Basically, I don't care what screensaver is running, as long as there is one running. Is that possible?

Solution 1:

On my 2008r2 DC, under User Configuration\Policies\Administrative Templates\Control Panel\Personalization I can select Enable Screen Saver, Password Protect Screen Saver, and Screen Saver Timeout without specifying a screensaver itself. Force Specific Screen Saver is different.

Solution 2:

In order to lock a workstation after X minutes, you should just need to set the three options below. This will not require configuring a specific screensaver.