Yosemite: Turning off Macbook Pro screen (lid open) with external monitor connected

No, idea. I use automatic login so I never have to type my password

My "perfect solution" for keeping the macbook lid open but internal screen switched off/only using secondary screen, even with power unplugged(!):

simply using two terminal commands

http://osxdaily.com/2011/09/14/disable-the-internal-screen-on-a-macbook-pro-or-a ir-in-mac-os-x-10-7-lion/

enable "screen off": sudo nvram boot-args="niog=1"

disable clamshell in yosemite: sudo nvram boot-args="iog=0x0"

The trick - putting Macbook to sleep and waking up (unplugged):

1. (when unplugged) simply close the lid to put Mac to sleep.
2. to wake up; plug in power and wake up with keyboard/mouse (or any external USB/firewire/bluetooth device).
3. Macbook wakes up, secondary screen turns on -> open lid (internal screen should stay turned off), unplug power.
4. Voilá! -> only the secondary screen is on and you can use the trackpad and keyboard if you want from your macbook.

If I am completely honest, I don't know how to use terminals and such, but if it helps anyone when I hook up my mac to an external display (in my case a tv) and want to turn off my monitor when streaming (Netflix for example) I just have to turn the brightness on my screen all the way down. The last setting turns the monitor completely off while the tv continues to act as a display (the brightness settings of my monitor do not change that off the tv). I'm not sure if this is the same for other displays however. I hope this may help anyone else.

Hi Aristi22, this is not exactly the same as most of the above mentioned solutions. When dimming the screen, the screen is still "on" as can be seen in the System preferences -> Displays section.

Some people only want to use the external screen in specific situations to improve performance or to simply use another screen (instead of the internal macbook screen).

In your case you're actually mirroring your internal display and dimming it. This results in a lot more CPU load of the graphics card, which most of the people in this thread want to avoid. Another reason might be when you just want a "desktop" with one ("extended"-external) screen. Hope this clears things up!

Please add this option in the OS X 10.10, I just melt the MBP 17" 2011 discrete card for not have this option to turn off the MBP display when I connect to the Thunderbolt Display, Now I have to pay a New Logic, because First it's a bad design of cooling the MBP 2011,

2011 MacBook Pro and Discrete Graphics Card

and second because there is not a option to turn off the display of the MacBookPro and force the card to work the double and that mean more temperature in the MBP for nothing.

Guys I just found this software and its doing the job for me. It lets the Mac working with closed lid. I am using external keyboard anyway so i dont need my lid open. Here is the link: http://osx411.com/how-to-keep-macbook-pro-laptop-awake-while-lid-is-closed/

The brightness on my external display (HP ZR24w via DVI) doesn't appear to be affected by the brightness setting on my laptop, so I just turned down the brightness on my MacBook to zero and voila!

--Ed

No, this does not turn off the native display. The GPU is pushing pixels all the same whether you dim the display or not, and this still shortens the life of the GPU with extra heat, even if the lid is open. Not only that you will lose a substantial amount frame rate.

This has been an issue since Snow Leopard and was one of the reasons I sold my Apple equipment. Very annoying that it is still the same problem today when I am working on a project with a Macbook pro. There is a class action lawsuit regarding the graphics cards, but I am not sure if clamshell mode being disabled in 10.6 was an argument to the case.

Yes, I understand. Sorry, I was only looking for a was to turn of the screen so that it wouldn't distract me. I was using my laptop keyboard while connected to an external screen with the laptop display folded back as far as it would go. I only need the screen to be visually dimmed. Not concerned about GPU usage or heat. Tks --Ed

The magnet works! How can anyone possibly advise against that?

For people who think a magnet is bad-THERE IS A MAGNET IN THE DISPLAY! It's not like the magnet in the display is suddenly NOT a magnet when the laptop is closed.

If you run your macbook in clamshell mode, you DO have a magnet resting on your computer!

If you don't believe it, run a paperclip along the edge of the display until you find the spot where it sticks. Badaboom...

If you can't get this to work, look at the code you are using very closely.

I found the code here: http://raynfire.net/2014/11/16/yosemite-how-to-turn-off-the-macbook-screen-lid-o pen-with-a-connected-external-monitor/

On that page, one character that should be " — decimal HTML " — is apparently ” — decimal HTML ”. Thus, if you are entering the command line

sudo nvram boot-args="niog=1" be sure you have not selected and copied and pasted bad code such as (red for emphasis)

sudo nvram boot-args=”niog=1″

I wasted most of a morning rebooting and trying to understand how you all were getting help from the command line and I was not. Here is a link to a site that posts the correct code: http://mac-how-to.wonderhowto.com/how-to/turn-off-macbook-pro-screen-with-lid-op en-and-using-external-monitor-0158393/

At least one site does not use the quotes at all in the example it gives. I have not tested that method, but the one I detail here worked for me on my MacBook Pro 9,2, under OS 10.10.2

My paperclip found 9 magnets, two groups of 4 at the top left and right of the display, and one about halfway down the left side of the display.