16-inch MacBook Pro on macOS Catalina 10.15.5 - Closed Lid/Clamshell mode issue

rogerwilco · 06-08-2020, 03:55 PM

Hi everyone,

I have been consistently having this issue and I will describe it below:

I have a MacBook Pro 16-inch, connected to a Dell D6000 dock through the USB-C cable.
There is a Displayport cable that is going from the D6000 dock to my monitor, an LG 34-inch 34UMCC monitor.
When the laptop is in clamshell mode and connected to the dock, I can see things on my monitor and the driver is working correctly.
However, if I reopen the lid, extended display doesn't work. The laptop screen is black and the LG monitor is frozen. Moving the mouse does nothing, press keys on the keyboard does nothing. The computer just freezes and I have to do a hard reset. Every single time. It is very consistent in this regard.
I have seen this happening consistently in macOS Catalina version 10.15.5 and the latest DisplayLink Driver, version 5.2.4 .
The only workaround I have found to work is to disable "Automatic Graphics Switching" in the Energy Saver, System Preferences pane. In other words, if "Automatic Graphics Switching" is enabled, the issue persists. If it is turned off, the issue goes away. So, I think there is an issue within macOS Catalina or the DisplayLink driver that isn't allowing communication between the 2 GPUs leading to a frozen system. That is just my thoughts.

Here are the specifications of my machine and the DisplayLink Driver:

16-inch MacBook Pro (1 TB storage, 16 GB RAM, Core i9 CPU)
macOS Catalina 10.15.5
DisplayLink Driver version 5.2.4

Let me know how I can help!

06-08-2020, 03:55 PM	#1
rogerwilco Junior Member Join Date: Jun 2020 Posts: 1	16-inch MacBook Pro on macOS Catalina 10.15.5 - Closed Lid/Clamshell mode issue Hi everyone, I have been consistently having this issue and I will describe it below: I have a MacBook Pro 16-inch, connected to a Dell D6000 dock through the USB-C cable. There is a Displayport cable that is going from the D6000 dock to my monitor, an LG 34-inch 34UMCC monitor. When the laptop is in clamshell mode and connected to the dock, I can see things on my monitor and the driver is working correctly. However, if I reopen the lid, extended display doesn't work. The laptop screen is black and the LG monitor is frozen. Moving the mouse does nothing, press keys on the keyboard does nothing. The computer just freezes and I have to do a hard reset. Every single time. It is very consistent in this regard. I have seen this happening consistently in macOS Catalina version 10.15.5 and the latest DisplayLink Driver, version 5.2.4 . The only workaround I have found to work is to disable "Automatic Graphics Switching" in the Energy Saver, System Preferences pane. In other words, if "Automatic Graphics Switching" is enabled, the issue persists. If it is turned off, the issue goes away. So, I think there is an issue within macOS Catalina or the DisplayLink driver that isn't allowing communication between the 2 GPUs leading to a frozen system. That is just my thoughts. Here are the specifications of my machine and the DisplayLink Driver: 16-inch MacBook Pro (1 TB storage, 16 GB RAM, Core i9 CPU) macOS Catalina 10.15.5 DisplayLink Driver version 5.2.4 Let me know how I can help! Last edited by rogerwilco; 06-08-2020 at 07:02 PM.