How do I tell Lion to disable the LCD screen even when the lid is open?

Please don't make judgments about people on this forum.

We are clear that you are happy with the state of affairs as they are. Others have legitimate (at least for them) reasons to feel differently. Scientific measurements of speed and temperature have shown that, at least for some, leaving the lid closed is not a solution they feel is workable.

We're trying to help each other out. If you're happy as is, that's great. No need to resort to namecalling. Just move along. Nothing to see here.

Apple could solve this whole thing with a simple switch in the Displays preference panel. They choose not to. I think that's silly, but apparently they have their reasons.

A magnet at a strategic place will solve the problem completely (and it is how I choose to address it), since it is activating a hidden switch. Some don't like this because it doesn't look right. Some think it is dangerous, especially if the screen is accidentally closed. Yes, that is a risk.

Others are looking for software workarounds or similar. Sometimes they work, but are prone to being obsoleted by OS upgrades. If and when they work, they are great, and are how many choose to solve the problem.

This forum is helping people share tips in order to work around what many feel is a silly Apple constraint. It is doing its job. Get out of the way if you don't have anything to add.

Yip, you're right. I wanted to feed the troll, but after reading your answer, I knew I shouldn't. Thanks for that 8o)

There are people, that never had Xcode indexing a huge project or playing HD-movie while Skype was on or played a game with the lid closed. I didn't find the official text, that was warning about temperature-issues in closed clamshell-mode. But in fact, that's not needed, as all persons experiencing this situation as a problem, know why it actually is one.

I just posted something helpful. Repeat: this isn't an issue, and the heat generated when closed are within specifications. Chips and capacitors are able to reach temperatures above 100 degrees celcius without harm. If they become too hot, they are throttled or shut down. If you're not experiencing this - which you shouldn't be unless you have a major hardware issue, you're ok.

I'm a developer, and I also love to boot up a game of Civilizations or whatever else on my MacBook Pro. No harm done closing the lid to play on the 27" Thunderbolt screen (or any other screen you'd have). You're not wrecking anything... and if closing the lid makes that big of a difference to wireless reception I'd have to think your wireless setup could potentially use a tweak in the first place. In my usage scenario (and I realize not everyone is the same...) when I'm docked I'm also using the ethernet connection versus wireless.

So, for others in this thread... my differing opinion and experience might help them to not worry so much as this is generally not an issue 🙂

Cody, you should honestly be banned for what you just posted. Software controls on safe heat ranges are not a protection, they are the last resort.

Running your hardware at elevated temperatures for too long, even in the "safe" range, will drastically shorten its life. Yes, hardware shuts down automatically if it exceeds certain temperatures, but any overclocker will tell you how useless this is in protecting your hardware.

If you run your macbook continuously with the lid closed, you are going to have a major issue. It is just a matter of time. Just like if you drive everywhere in 2nd gear.

Again... there's no proof that operating your MacBook in clamshell mode is drastically increasing temperatures to unsafe levels, nor increasing it enough to show measurable differences in component lifespan. This might make a difference if you ended up with one of those nVidia 8800 series GPU's that were failing due to manufacturing error.

Ok Cody, you are an electrical engineer too I'm sure.

Apple tells you not to run it with the cover closed. This is comon sense, you probably leave your iPad out in the sun then get mad when it overheats and fries. "But it wasn't even hot out."

My concern is poor wifi signal when the lid is closed (while using the external monitor).

codydhorner wrote:

nVidia 8800 series GPU's that were failing due to manufacturing error.

Just an fyi, those are 8600 GPUs.

Another note: I don't understand how anyone can tell anyone else that their personal preferences (operating with the display open) are wrong. Can I tell you that liking chocolate is wrong???

My mistake, 8600. Nobody is saying anyone's personal preferences are wrong - just that Apple obviously hasn't designed things with this in mind outside of what they've already done which are:

1) allow you to black out the LCD with the brightness controls on the laptop keyboard

2) run it in closed clamshell mode

Does it seem odd to you Apple would provide this feature to run on dedicated graphics in clamshell mode only to have it wreck a bunch of their machines? Would that not create a huge issue of costs in the warranty replacement department? I've never used a laptop in my life that has died from using it in clamshell mode... nice little maxed

MBPr I have (2.7/16/768) and use in clamshell mode sometimes for the odd game or two. I guess I should be more worried about my ~$3,800 machine. What I'm saying is: this isn't a big deal.

For the last time... I just don't see how this is a big deal to just use the system and OSX as it is without trying to come up with some sort of reliable hack. Again about the wireless... if you're running with the lid closed, and you've got it hooked up to your "docking station" there are many other solutions to improving your wireless performance (or the internet connection in general) than hacking OSX to turn off the display while the lid is open.

End of my input on this thread. Silly 😉 And no I'm not an Electrical engineer, and neither are you (though I did become a professional programmer as my day job somehow.... wink). And I don't own an iPad as I have no use for one. However, if I did. I'd not leave it out directly in the sun and get mad when it overheats lol ... you must be a good few years younger than I am pal. Again: why would Apple explicitly enable a feature which is clamshell mode, if it was a surefire way to destroy the machine? Some of these laptops run hotter yes... but what about having the lid closed impedes the airflow? On my system in specific, it actually improves airflow since when the screen is open, the air stream is partially obstructed by the bottom of the screen chassis.

Just for you kiddos reading:

http://support.apple.com/kb/HT3131?viewlocale=en_US&locale=en_US

Apple tells you how to use clamshell mode. 😉 Cheers!

Nevertheless a group of users asks the manufacturer of their choice to provide a feature, all competitors on the market provide.

If you can't accept technical reasons, you can't argument against the users' convenience. We want it for convenience.

The effort to provide the feature is negligible. It would make many users a lot happier and wouldn't disturb the other users not needing it. It's simply arrogant to ignore it.

I'm so tired of parenting IT-geeks, thinking, they have to discipline the users to their religion.

When closing the lid you are reducing the surface of the aluminium body that gets a cooling effect by being exposed to air. Instead, the heat goes into the lid and from there into the air reducing the cooling effect and leading to higher temperatures in the lid. Even the few milimeters between the backplate and the surface are really important to cooling, as there is airflow by thermodynamics. That's why the device runs at higher temperatures, when using it in bed or on a carpet.

Imagine the MTBF is somewhere above 3 years (Apple Protection Plan). By not telling the customers, using the product in closed clamshell mode will reduce the lifespan (not below 3 years), the device dies earlier, but still beyond 3 years. Effect: Company doesn't have to pay anything but customer has to buy a new device.

But sure, without any doubt, Apple has only good products and their users in mind, not pimping their number of sales.

Back to the topic: We would like to have the feature to simply switch off the internal display (not just backlight) without having to close the the lid.

-_-

sigh.

This trolling has gone long enough. First off qualifications for the old dude and accidental programmer, I am a computer engineer who worked as software engineer for 10 years. Now with that out of the way, a real world story. My first macbook was a 2008 white polycarbonate. I owned it for two years and clamshelled most of the time. I noticed after two years of constant use (Xcode and Starcraft 2 among others) that the battery has swelled up. Sort of like this short-070405-1.jpg.

Last year I bought a new MBP and have been really conscious about the temperature. I've been measuring it in clamshell mode while doing CPU intensive tasks such as Photoshop and games and I've noticed that in clamshell mode the temperature increases to at least 140ºF to 160ºF maybe higher, I never bothered to wait for it to peak. While operating on open case with primary screen turned off the temperature would be 20º to 30º cooler. Now most folks in colder climates would not get similar results because their ambient temperature are much cooler, but even though I'm using AC, those are the results I'm getting.

Given those facts a bloated battery is one thing, I would not risk broken motherboard on my MBP. Just allow us to turn the primary screen off when an external screen is connected and we'll be happy. K tnx bye!

Oh to codydhorner, your posts are honestly very irritating. You're not helping, the people who post in this topic have experienced, one way or another, problems when operating in clamshell mode. We are QUITE AWARE that you think that clamshell mode is okay. This topic is to address issues, and not contradict other peoples experiences and claim it's a non-issue just because of your limited experience with the issue. Honestly, you sound like a programmer who says a bug can't possibly happen until the QA humiliates you by pointing out exactly how it's done. Again, these forums exist to help people out and not to contradict them. YES WE KNOW about clamshell mode and YES WE'VE TRIED IT and most of the people here had BAD EXPERIENCE with it. If you don't have any other solutions for this other than clamshell mode, we would rather not hear from you again. I wish these forums allow you to report users. sigh.

****!!

I've trying not to updated to 10.8.2 since I read here that the trick didn't works anymore, bu t I finally had to update and Im with the internal display active again!!!

when I'm working on my desktop, I have my cintiq and my 24" dell, and of course, the macbook internal display on, wasting GFX power

I recently accidentally discovered a way to turn off the primary display on my MBP late 2011. Confirmed that this trick works on OSX Mountain Lion 10.8.2. Note: If you ran the NVRAM command line hack before this then you would need to disable it. See the solution posted by chenga.8 in: https://discussions.apple.com/thread/3190417

This method has been posted somewhere in this thread earlier, but wasn't able to do it earlier. First thing that you need is a game app that has a full screen mode (Note: not windowed full screen but actual full screen). Games I've used for this tricks are Warcraft 3, Zen Bound 2 and possibly Civilization 4 (not quite sure about the last one). Any game could work as long as it blackens the primary LCD when the game goes full screen. Here are the steps:

1. Close the lid on the MBP, this will put it in clamshell mode.

2. Run the game in Full screen mode.

3. While the game is running, open the lid of the MBP. You will notice that the primary screen is still turned off.

4. Quit the game.

You'll notice after the 4th step that the primary display of MBP is still turned off after you quit the game. When you need to restore the primary display, just close the lid and open it again when no fullscreen game is running. Enjoy.