How to Turn Macbook monitor off with lid open?

[Macario]

I want to work on my MacBook connected to an external screen, keeping the MacBook's LCD off even though the lid is still open. I use an external monitor via mini DVI and connect it to 21 inch monitor. I have recently upgraded to Mac OS X 10.6.3 but I am unable to turn off my laptop display anymore. Is there a way I can configure my Macbook to stay running when I close the lid? Do anyone have some advise for me on how to accomplish this?

[BansiJ]

There are many ways to shut down your Macbook screen. The easiest would be by pressing Shift-Control-Eject. The Eject key is present at the top right corner of your keypad which allows you to turn off your screen. There is yet another possibility, you can just close your lid like any other laptop and use it in a clamshell mode. It allows you to use your Macbook while the monitor is not in use. You can also use a software which is well known for shutting down your display. Its called Sleep Display. You can add it as a widget to your Macbook, however the only problem is that it might also turn off your monitor.

[Pugsly]

I have a best option for you. Macbook has an built-in feature that can bring the brightness of your monitor all the way down until the backlight shuts off and the display goes blank. All you have to do is press F1 key. But why do you want to close it down? You can keep it running even though you are working on another monitor. Macbook is designed to be cooled in any situation. Macbook will be in constant sleep mode until you disconnect your mini dvi cable. If the Macbook brightness is causing you the problem then you can anytime turn the brightness of your screen all the way down.

[switchblade327]

Apple has a feature that makes the secondary monitor to go blank when the Front Row is started. For this you have to make your secondary monitor as primary. To do this go to the System Preferences - Display Preferences. While you have your mini DVI cable connected to your MacBook and to the external monitor, open up Display Preferences and select Arrangement. You will notice two squares representing each display. The one which is the main display will have a bar at the top. To make it secondary you have to simply drag this screen to the right hand side. This will ask your operating system to make it secondary and the other as primary screen. You may now close Display Preferences. Now you can start Front Row by pressing Apple key + Esc. You will notice that your primary display goes down while your external monitor is working and showing your Mac desktop.

[Macario]

Thank you for your answers. What happens is when I close the lid my Macbook gets much hotter than if I leave it slightly open.I even noticed that the motherboard fans were running much more faster than they usually does when the lid is opened. That's ridiculous if you need a second monitor connected to your Macbook. We doesn't have an option for the computer to run with the lid down. Is there any other way to turn the laptop display off while the lid is open? And by the way how can I use my Macbook in clamshell mode?

[Gonzo]

I am not so sure about the fact but I think the MacBooks use the keyboard as part of air flow, so if you close the lid then it may cause it to run slightly 'hotter'. Keeping the lid closed all the time will raise the temperature a few degrees. So according to me you may want to look for some other alternatives. However if you are thinking that you can save some CPU time or cool it down by closing the lid or doing anything else then that's totally wrong. The LCD itself will still be functioning even if you turn the backlight down. However, if you close the lid then it might go in to the sleep mode.

[Simond]

You can run your MacBook in lid-closed mode. But for this you need a keyboard and mouse. To use your Macbook, connect your mini-DVI to video adapter and connect it up to your external monitor. If your Macbook is in extended-desktop mode, you have to configure it to video-mirroring mode. For this you can either press F7 or Fn-F7. You will notice a change in the resolution of your main display and your external monitor. You will also see the same screen on both the displays. You can now close your MacBook lid. You will notice that your Macbook goes into Sleep mode. Now press any button on your Apple Remote and your MacBook will wakes up. Press Menu button to enter into Front Row. This is also known as clam shell mode.