Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I'm trying to setup a duplicate display on Windows 7, on a Lenovo W520 laptop. The goal is to output the main desktop to both the laptop screen and a VGA projector. I believe the laptop has a dual video card setup, one Intel card and one NVIDIA card.

So far, Extend works, as does projecting to just the monitor or just the projector. However, when using duplicate, the picture only ever shows up on the laptop screen.

I have tried every option I can find in the Windows displays panel, in the NVIDIA control panel, and in the Intel Control panel. Nothing seems to accomplish this.

I'm thinking the problem has to do with the two different video cards, but I'm not sure. Has anyone tried this before?

Incidentally, in the Windows control panel, the only options shown for duplication are "Duplicate Desktop on 1 and 2" (does not duplicate), "Extend desktop on 1 and 2", and "Show Desktop only on 1" (or 2). None of these are the right option.

share|improve this question
Silly thought - you're sure when you set duplicate that it's sending a resolution the projector can support? That sounds like the likeliest problem to me. – Shinrai Dec 9 '11 at 15:20

I am curious if you have tried the FN/F4 combo. Usually any laptop is going to have one of the number keys or one of the Function keys set with a FN function to shunt the display. I think on most Dell's it's FN/F4 or F8 but either way there should be a little graphic on that key in the color of the FN key that looks like a screen and a laptop that is half opened or some such.

I don't know that this will "fix" you but I'd be interested in the results from whacking that combo a few times...

share|improve this answer
This is Fn+F7 on all Thinkpads. Also, Win+P works on any Windows 7 machine. – Shinrai Dec 9 '11 at 15:28
I guess as I sit here pondering I also am curious at the resolutions you are using when you are trying the duplicate. Is it possible your projector won't meet that display resolution and so simply fails and with no error? Maybe try hooking up some other external display and see if you can make that work or even get it going as it has malfunctioned already and then start trying different resolutions? – OG Chuck Low Dec 9 '11 at 15:32
I can't see the computer right now, but I know the duplicate resolution is supported. The projector supports everything up to 1024x768 officially, and scales down higher resolutions to 1024x768. The monitor to duplicate is at 800x600 (low, I know...). – gjsmo Dec 10 '11 at 0:20

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.