Black screen (power saving) is not coming up on login screen
I have a few machines set up and running Red Hat 4.1.2-42 in a computer lab. I also have a single test machine running the same version. The machines in the lab work flawlessly. However, when machines are on the login screen, they don't go into power saving mode. That is, after a certain amount of inactivity, the idle login screen should be replaced by a black power saving screen. But this does not happen. The monitor should go into standby (the little green light becomes orange, and the whole screen shuts down until you move your mouse again...you know the drill).
I know this is supposed to be the case because this works on the test machine. It just doesn't work in the lab. I think it has something to do with gdm, but I can't for the life of me figure it out.
Any help is greatly appreciated!