Phantom 3rd Screen

[cshbell]

Originally Posted by Carlo

We've been able to reproduce this issue some time ago on 10.7.2, but when we retried last week on the same system we could not see the issue. We'll be trying different power saving options and login options to see if it has any effect. You are welcome to help finding the exact use case!

As others have reported, it's pretty easy for us to reproduce. I'm on a mid-2011 MacBook Air (4,1; i7 11-inch) with 10.7.3, and stock software preload (no odd kernel extensions or drivers). Here are the power settings from System Information:

AC Power:
System Sleep Timer (Minutes): 0
Disk Sleep Timer (Minutes): 10
Display Sleep Timer (Minutes): 0
Wake on AC Change: No
Wake on Clamshell Open: Yes
Wake on LAN: Yes
Current Power Source: Yes
Display Sleep Uses Dim: No
PrioritizeNetworkReachabilityOverSleep: 0
RestartAfterKernelPanic: 15
Standby Delay: 4200
Standby Enabled: 1

Battery Power:
System Sleep Timer (Minutes): 15
Disk Sleep Timer (Minutes): 10
Display Sleep Timer (Minutes): 15
Wake on AC Change: No
Wake on Clamshell Open: Yes
Display Sleep Uses Dim: No
Reduce Brightness: Yes
RestartAfterKernelPanic: 15
Standby Delay: 4200
Standby Enabled: 1

Using a BVU195 DisplayLink adapter; I see this problem whether I'm connecting two 19-inch LCDs in one location or one 20-inch LCD in another.

And as others have said, steps to reproduce:

1. Boot the MacBook with the lid closed, power adapter attached, external keyboard (Apple Bluetooth keyboard, in my case), and an external monitor attached to the DisplayPort/Thunderbolt port; does not matter whether or not the DisplayLink adapter is connected. Only the external monitor will be enabled at this point, as desired.
2. Now disconnect the power and external monitor from DisplayPort/Thunderbolt port, causing the Mac to sleep. Wake it back up from sleep. Only the internal LCD will be enabled at this point, still as desired.
3. Now close the lid, reconnect power, external monitor, and keyboard, press a key on the external keyboard to wake the system up. The external monitor will be enabled, but so will the internal LCD (and the Apple logo is illuminated from the internal LCD's backlight being on). Not desired.

Let me know if you're able to reproduce it following these steps. I'll even make a video of the process if that will be helpful. Please try and help us out with this.