Comment 42 for bug 1245474

I've read through the portions of Xorg that are directly related to the screensaver timeouts (dixSaveScreens() and friends) and it appears that my suspicion is incorrect. I was unable to find any sort of built-in default screensaver. Another dead end.

Then I remembered that the kernel has a built-in screensaver. This appears to be leading somewhere now. In 13.04, you can adjust the login screen timeout by adjusting the terminal blank timeout. Log out of all X sessions (in 13.04) and go to VT1 (Alt-Ctrl-F1). Then login and use setterm to adjust the blank timeout to 1 minute.

  $ setterm -blank 1

Now, switch back to VT7 (Alt-F7) and wait one minute. The display will power off (in 13.04).

This doesn't work in 13.10. However, it does work for the other virtual terminals in 13.10. So, it's as if the kernel's terminal blank feature is somehow set up to have no effect on Virtual Terminal 7. Assuming I'm on the right path, we should have an answer soon.