5 Replies Latest reply: Mar 26, 2008 12:20 PM by Glen Doggett
Vicci Conway Level 1 (0 points)
Hi, I have a new MacBook and want to connect an external monitor.

How do I find out which monitors it works with?

I have a ViewSonic 24" and someone mentioned the limitation on a MB is 22". How does it know it's bigger? Why wouldn't it just display on part of the screen? It displays nothing.

So, back to question 1 - so I know what monitors will work. Do I need to find drivers?


MacBook, Mac OS X (10.5.2)
  • BSteely Level 5 (7,635 points)
    So you have plugged your MacBook into your ViewSonic 24" and you are getting nothing? What interface are you using? Does the MacBook seem to detect the display at all? Is it showing up as a second attached display in Displays preferences?
  • bdkjones Level 4 (1,330 points)
    The MacBook is capable of driving a display that uses SINGLE-link DVI. Anything larger than 23" generally uses DUAL-link DVI.

    (Dual-link provides extra bandwidth which is required for calculating the larger number of pixels on bigger displays. Smaller displays have less pixels and therefore require less data to be transmitted to the display and thus can use lower bandwidth connections.)

    If your monitor requires Dual-link DVI to drive it at native resolution, your MacBook will not work with that display.
  • Vicci Conway Level 1 (0 points)
    Hi, thanks for replying. My screen on the MB goes blue for a second as if it senses something, but it gets no picture on the external monitor. It has a DVI connector; I purchased the DVI to mini DVI Apple connector. I'm checking for the dual thing now based on another response here. I also tried to the Detect display and got nothing.

  • BSteely Level 5 (7,635 points)
    The dual-link thing is unimportant in this case. That only applies to 30" monitors with very high resolution. Your 24" monitor has 1920 x 1200 resolution, which is the same as Apple's 23" Cinema HD Display and both are single-link DVI compatible.

    I would try doing a reboot with the external display attached and see if that helps.
  • Glen Doggett Level 4 (1,840 points)
    If the monitor has multiple inputs, i.e. DVI or VGA, make sure the front panel or on-screen menu on the monitor has selected the appropriate source that you are connecting to the MacBook. (rebooting is a good idea, even though the mini-DVI might supposedly be hot-swappable.)

    Does System Preferences: Displays: Arrangement show that the MacBook thinks the external monitor is present?