« Milton Friedman, Economist | Main | Fujifilm F30 Camera »

Display problem with laptops: Mirroring vs Extended Desktop

I was having problems with my Dell Latitude D600 laptop. I had used it in extended-desktop mode for a while, with an external monitor connected. Today, I wanted to use it for a presentation, with the projector mirroring what was on my laptop screen. It failed to work… No matter how many times I pressed the Fn-F8 (CRT/LCD) key, the projector would just become an extended portion of the desktop (not a mirror). PowerPoint presentation mode doesn't quite work right on an extended desktop, so I was reduced to leaving PP in "edit" mode on the projector.

How to fix? This pdf (by Robert Ralston of UC Davis) has the path to the answer, under the heading "PC Laptops With ATI graphics".

It didn't work exactly as the pdf states, possibly because I have a slightly older laptop. (Or, maybe, because my projector works differently than his.) His instructions were to start with the projector on, as your second desktop. Use the Display Properties window and uncheck the "Extend Windows Desktop" for the projector (second monitor). Then, on the first monitor, click "Advanced", then "ATI Displays". The second monitor should have a red tab next to it.

Mine did not. It appears as though, when deactivated (when the "extend desktop" was unchecked), the projector detached from windows.

The solution was to start over. Start with the projector on as the second desktop, again. Click "Advanced" on either of the monitors, and go to "ATI Displays". Under the "monitor" quadrant, click the box to make it "Display 1". (Notice that the "panel", i.e. your laptop screen, becomes "Display 2".) Press "Ok". Now, you can pretty much follow the directions above. Go to monitor 2 (in the Display Properties) window and uncheck the "Extend Windows Desktop". This will turn your laptop screen blank. Then, click on monitor 1, Advanced, and ATI Displays. Click the red tab next to "panel". If you hit "Apply", then your laptop screen should re-ignite, and have the same contents as the projector. Success! It will work better if you click the button in the panel quadrant with the concentric circles, so that the laptop panel will be the "primary" monitor if you disconnect.



TrackBack URL for this entry:


And they pay you to do this? As a "paid presenter" for several years I must say that I never had this problem. Finding the right "F" button to cycle between desktop and projector was my biggest challenge. I hope the audience was kind as you worked on this knotty tecchnical issue :-)

Well, Tom, I think that the problem came about because I was doing some work with the laptop with a second monitor (extended desktop). I love the dual-monitor setup... More stuff can be viewed at once (rather than the constant shuffle between windows). Maybe my monitor-switching tangled my settings.

Fortunately, the presentation went well without the full PowerPoint presentation mode. After the meeting, I spent about a half-hour figuring this stuff out. Not a big loss to Honeywell, I hope.

I am having a similar problem with several Dell Latitude D810's, but the ATI Tabs don't appear in the Advanced window. Any thoughts?

EJ - You might want to check to see if Dell (or your video card manufacturer) has an updated video driver. Sometimes they add functionality.

You saved me. I was struggling for over 2 hours because it would keep resetting as the 'extend windows desktop' I have a dell with ATI monitor. Just use the ATI Control Center. Change to clone.

thank you. very clear instructions. solved a difficult problem i'd been struggling with.

THANK YOU for the tips, Jeff and Judi. Two hours later, I finally read this, and changed it to clone/mirror through the ATI control center in 5 minutes.

Post a comment

(If you haven't left a comment here before, you may need to be approved by the site owner before your comment will appear. Until then, it won't appear on the entry. Thanks for waiting.)