MBP still thinks Thunderbolt Display is on

Entertainer

macrumors member
Original poster
Jul 24, 2013
38
6
Brand new 2018 MBP and I have it connected to a CalDigit Thunderbolt (2) dock. Got my 34" LG U-whatever connected to the hub through HDMI. When I turn it off, the laptop still thinks it's connected as I can move the mouse out of the screen of the Mac and I can still see the other monitor in Display settings. I'm guessing it's using system resources to power this external display, not good. Any ideas on how to tell it to disconnect?
 

Entertainer

macrumors member
Original poster
Jul 24, 2013
38
6
No ****, I never thought of that!

The HDMI plug is inconvenient to unplug form both ends. I connect and disconnect my laptop frequently.
 

iMacDragon

macrumors 68000
Oct 18, 2008
1,861
350
UK
I'm guessing the display probably needs to be fully powered off from mains to no longer report as connected, in standby mode hdmi port is still often active I believe.
 

DeltaMac

macrumors G4
Jul 30, 2003
10,272
2,700
Delaware
You could also turn mirroring on, so the only screen you use is the one you see (and not an extended desktop).
Turn mirroring off when you use the external. You can keep that choice in your top menubar.

But, I agree, the LG display port must stay energized, even if the display is powered off. If it is not convenient to disconnect the video cable, maybe all you need to do is disconnect the monitor from power. A switched AC power strip should do the job for you.
 
Last edited:
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.