Mac Powerbook and external monitors

I’m helping a few faculty members at my university when they need to use technology in the classroom. I write HTML presentations and put together Powerpoint presentations for them, set up the course website, and do a few other low-level techthings. I not a proper tech support person, just someone who knows enough to help out the non-tech-savvy profs.

Anyway, i now find myself with a very simple problem:

The new classrooms on campus all have excellent computer setups, with PCs connected to large screens for faculty use and student viewing. There is also a VGA connector so faculty can attach their laptop computers to the system and display the laptop screen on the large classroom screens.

Now, once a laptop has been connected to the system, it usually requires pressing a couple of keys to get the computer’s desktop to display on the external monitor. I know how to do this on a PC, but one of my faculty members has a Mac Powerbook, and i couldn’t for the life of me work out how to do it.

Can anyone help me with what i’m sure will be a very simple solution to my problem?

Don’t have one myself, but did you look in “System Preferences” (under the Apple menu in the upper-left corner), under “Displays”?

This is assuming you’re running some version of OS X.

In the displays preference panel, there should be a button that says “Detect Displays.”

Thanks folks. I’ll try that and let you know.

I thought that the owner of the computer would know how to do it, but it’s a brand new machine and he only made the switch to Macs a weeks ago.

Make sure the dual display mode is set to “Mirror Displays,” otherwise the OS will try to use the external screen as a second desktop, and the external monitor may not work at all. Had a little trouble with that at my job recently until I figured out what was going on.

If you hook it up while the PB is shut down and then reboot, it should mostly “just work”. (You may need a visit to the Displays PrefsPane to tell it to mirror. It may arbitrarily select the external as primary and use the interal TFT as an auxiliary monitor, for instance, especially if there’s more total screen res on the external).

By the way, it all works with Mac OS9 (and earlier) in the unlikely event your professor is using an older PowerBook. The configuration tool would be either the “Monitors” or the “Monitors and Sound” Control Panel rather than the “Displays” PrefsPane in that case.