Help with Laptop Projection

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Laptop projection problems (Mac or PC)

Please see this page for tips on solving laptop projection problems: Projecting_from_your_Laptop_Computer - What_to_do_if_Your_Computer_doesn't_project

Computer Resolutions

Some information on computer resolutions:

Name Pixel array Aspect ratio Comment
VGA  640x480 4:3
SVGA  800x600 4:3
XGA  1024x768 4:3
WXGA 1365x768 16:9 Wide-XGA; used for wide screen LC TV displays (beware: sometimes 1280x768 is called WXGA)
SXGA  1280x1024 5:4 squarer image and will not display correctly when projected onto a 4:3 aspect ratio screen.
UXGA  1600x1200 4:3
QXGA  2048x1536 4:3

Apple Color Profiles and Projection Issues

Issue: We've had many an instance where the Mac's default color calibration (most likely gamma) was too dark when projected on a projector (but fine on the Mac's internal display).

1) Connect to the projector or display where the issue is obvious.
2) Click on the Apple logo and select System Preferences > Displays.
3) There will be two windows with color settings. Click on the one NOT named Color LCD.
4) Click on the Arrangement tab and place a checkmark next to "Mirror displays" (if this checkbox isn't already checked).
5) Click on the Color tab and select Generic RGB. This should brighten the image displayed through the projector. If this doesn't resolve the issue, try some of the other options next to Generic RGB. If that doesn't help, you may need to follow these instructions: http://support.apple.com/kb/ht3712

Laptop Projection Shortcuts

Dell with Windows XP: Fn+F8 (or F6)

Any Windows 7 computer: Windows Key + P

Apple: You can also try pressing Command (that's the apple key) + F1 or F7, though Apple has been trying to discontinue this shortcut.

PC Laptop Audio & Displayport Problems

When you are trying to project from a PC Laptop using the HDMI or DisplayPort, this function is trying to send the video and audio signal through the same cable (HDMI or DisplayPort). In situations where the audio and video are on a separate cable, this is not going to work because you will not have any sound.  

You will need to change the default adio settings. Go to:



Control Panel

Sounds and Audio Devices


Then under the Default Device selct the IDT Audio option. 

Click apply and then Yes to save new settings.  

What do the analog sunset and digital audio/video mean for Middlebury?

The media and computer industries have chosen to retire analog audio and video and move to digital audio and video. This is the death of VHS, LaserDisk, 3/4" tape and our beloved VGA and maybe even 16mm and 35mm film. Blu-ray, Internet video and HDMI are the new formats that are meant to replace all of the aforementioned media formats. The DVD format will remain alive, for now. On one hand, we think the addition of Blu-ray and Internet video in our classroom will be reasonably straightforward. All computers distributed by Middlebury College can play internet video and we are adding Blu-ray players to classrooms every year. On the other hand, HDMI will be harder to implement, at least at first.

HDMI is a new type of audio/video connection that allows audio and video to be sent over the same cable. DisplayPort (used by some Dell computers) and Mini DisplayPort/Thunderbolt (used by most modern Apple computers) are additional audio/video connection types that are supposed to be compatible with HDMI and are supposed to sendboth audio and video over the same cable. Both HDMI and DisplayPort aim to reduce audio/video projection complexity and reduce cable clutter. Moreover both of these connection types allow for much higher quality projection.

Of the two, Middlebury has chosen to support HDMI alongside the existing video cables (VGA) for the foreseeable future. Thus, any classrooms built or upgraded after May 2009 will support both HDMI and VGA. This decision was made based on the media industry's decision to support HDMI, Dell's current and future choice to use HDMI and Apple's promise of compatibility between their Mini DisplayPort/Thunderbolt and HDMI.


  • some computers distributed by Middlebury College have a VGA connector only (mostly Dell computers made before 2010)
  • other computers distributed by Middlebury College have a DisplayPort and VGA connector (mostly Dells made between 2010 and 2011)
  • a third group of computers distributed by Middlebury College have an HDMI and VGA connector (mostly Dells after 2011)
  • a fourth group - most current Mac computers - can be connected to VGA or HDMI with the appropriate adapter.

Connecting a Mac computer to a projector or TV or monitor using HDMI

For Mac models that have Mini DisplayPort/Thunderbolt, it is possible to use an HDMI adapter to connect to some of our newer classrooms and project a much higher quality image. However, not all computers that have Mini DisplayPort/Thunderbolt can send the audio over the same cable as video due to incomplete design by the manufacturer. Right now, we are aware of certain Mac computers that cannot output audio over the HDMI cable. Roughly, this includes Mac laptops made before Mid-2010. There is no definitive list of these computer models that do not support audio over the video cable. There is, however, a list of Mac computer models that do support both audio and video over the HDMI cable with the appropriate adapter.

Potential audio problems when connecting a Mac to a projector using HDMI

We have noticed that some combinations of Mac computer + HDMI adapter + classroom projection system may produce valid video projection but no audio. Dana Auditorium is one location where this may happen. Here are some steps to remedy this:

  1. Ensure that you have firmly connected the HDMI cable to the appropriate HDMI adapter and that the adapter is firmly connected to your Mac computer.
  2. Click on the Apple logo in the top left corner of the screen and click System Preferences.
  3. In the System Preferences window, click Sound and under the Output tab, select the HDMI option. This should produce both audio and video projection.
    If there is still no audio, follow the next steps, as well.
  4. Click on the seach button in the top right corner of the screen and type Audio MIDI Setup. In the list of search results, click on the Audio MIDI Setup application.
  5. In the Audio MIDI Setup application, click on the HDMI option in the list of devices on the left. In the right-hand portion of the screen, ensure that Format is set to 48000 Hz and 2-ch 24bit. The settings take effect immediately - just close the MIDI setup application.
  6. Contact the Helpdesk if the above steps did not help.

NVIDIA Control Panel Settings

Some of our laptops were shipped by Dell with an NVidia graphics card that needs to be activated for projection and dual-screen use. See this article for details.