I had a similar problem in an old notebook years ago.
It only works when I pressed Windows + P and select the option Projector Only.
Still it blinked but stayed on.
If you pull out the right sidebar and pick settings, there's a menu item to go to your Control Panel. From there, access power options, and change your current plan settings. In the plan settings, you can adjust advanced options via the menu on the left.
From what I understand, under "Power buttons and lid" you will want to set the lid option to Sleep, and set the Power Button action to Hibernate.
If you want the lid option to transition into the power button option, you'll also want to go to "Sleep" and either enable Hybrid Sleep or set a timer for "Hibernate after" (which starts counting from when the computer is idle, not when it goes to sleep).
And you will also want to set require password on wake to off as well.
This should get you to your desired configuration. Unless you're running Windows 8 RT; I haven't even seen one of those so no idea how different they are.
Some elaboration:
Sleep puts your computer in a low power state, feeding power only to RAM and input devices, with periodic mini-wakes to check on scheduled tasks. Any action from input devices will wake the computer (which includes opening the lid). Waking from this state is usually faster, as your computer's state is still in RAM, and the computer only needs to reinitialize your other devices.
Hibernate saves your computer state to disk, and powers everything off. The only way to "wake" from this point is to power on the device. It takes a little longer to wake because it must read everything off disk into memory, and disk is the slowest data device.
Additionally, sleep usually doesn't need a password because it functions more like a screen saver than a screen lock. Hibernate requires password because it's as if you rebooted your computer, except it reopened all your applications into the state before power-off.
Best Answer
It is possible in Windows to disable the 'sleep' action on lid close. However, you may experience some heat dissipation issues due to the placement of the vents on the Asus Zenbook range being under the (now closed) lid. Here's how to do it anyway, but there is another option that I'll list below:
1. Disable Sleep Mode on Lid close
Press Windows+R, and in the 'Run...' box, type
powercfg.cpland press Enter. This will open the Power Options:Click the 'Choose what closing the lid does' link from the left side panel, and under the 'When I Close the Lid', change the setting to 'Do nothing' when Plugged in.
I recommend leaving the 'sleep on battery', as you'll usually want your laptop to conserve power whilst on the move.
2. Turn off the monitor (and leave the lid up)
Usually laptops have a button that disables the output on it's primary monitor, turning it off entirely. I cannot be certain if your Asus Zenbook does, but it's worth looking for as it's handy to have.
If it does not, this can still be done from within Windows. Right-Click your desktop and go to 'Screen Resolution'
You should see two example displays. Hit 'Identify' to show you which number represents which monitor, and then under 'Multiple Displays', select 'Show Desktop only on Monitor X', where 'X' is the monitor number you wish to use.
Click apply, and your laptop's screen will turn off, allowing you to use the other monitor as your primary monitor whilst docked.
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