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16" MacBook Pro with multiple displays -- lots of problems so far

I've got a three display setup like this:
  1. Center: LG UltraFine 5k, direct TB3 connection, with further connectivity to USB3 devices via a powered hub
  2. Left: ThinkVision P24q-10, direct USB-C connection, with some USB2/3 devices connected to it
  3. Right: P24h-10 via a Displayport-MiniDisplayPort cable <-> Thunderbolt 2 RAID drive <-> MacBook (using Apple's TB3>TB2 adapter)
I've had no problems with this arrangement. All displays and devices wake up just fine, so far. There's about a dozen peripherals and accessories connected through the monitors.

I'm waiting for a Caldigit TB3 Mini dock to arrive from mail. It will enable one less wire and will clean up cable routing in general. But let's see how well it will work.
 
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I have had similar problems on my new 16inch MacBook Pro with my Dell 32in 4k display (UP3216Q). All the display settings are forgotten when it sleeps / restarts... My main problem is that the refresh rate is then locked at 30hz instead of 60hz... there seems to be no logic to when the 60hz option comes available, you have to keep unplugging / replugging into different MacBook ports until suddenly it starts working... some times this can take half an hour of restarting MacBook / screen / toggling scaled resolutions... It's highly irritating.

This same setup worked fine on my previous 15inch, and I have the correct cable usb-c > display port 1.2 which supports 4k@60hz.
 
zed said:
I'm having a similar issue with the LG Ultrafine 5K display. Occasionally upon waking from sleep both the 16" MacBook Pro display and the LG display will flicker continually until I unplug the external display. Once it happens I am not able to get the external display to connect again without restarting the laptop.
Click to expand...

I had this with my LG 27-UD88 4K screen for the first time a couple of nights ago. It didn't matter which port I used, both screens just kept flickering.

Its never happened before and hasn't happened since - a reboot fixed the issue for me so it seemed to be a one-off.

I'm not using a dock, am just connecting via usb-c and my setup has been very stable since day one with the MBP - I've also not had any issues with cpu temps and fans blowing.
 
milhous said:
For those not using Thunderbolt 3 docks to connect their displays, do not use USB-C hubs/docks in-between the computer and the displays. Instead, directly connect displays with USB-C <-> DisplayPort/HDMI cables between the computer and display. When doing this, the computer switches that port into USB-C Alt Mode, which no longer makes it a USB port, but a dedicated non-USB port for carrying native display signals from the GPU to the display. When using a USB-C hub, the total bandwidth available to the hub is shared between all devices connected to that hub, in addition to routing a video signal, which in itself may be inadequate to drive the display(s) at its native resolution and refresh rate (and/or lead to other complications).

USB is CPU-dependent, so the more USB devices are connected to your computer and doing something, the harder the processor has to work to communicate with all of them (more heat and noisier fans).

While showing stats are helpful in diagnosing problems, it's also just as important to describe how exactly the displays are connected to the computer. Listing your setup in the signature section of your profile will help others help you faster, all while avoiding the need to repeat yourself.

More information:

HDMI Alt Mode for USB-C
DisplayPort Alt Mode for USB-C
USB-C to DisplayPort Cable (Example)
USB-C to HDMI Cable (Example)
Click to expand...
Thanks for this info brother maybe you can help me out:

I bought this dock at best buy
6357396_sd.jpg;maxHeight=1000;maxWidth=1000

and had to return it b/c DisplayPort wouldn't work. My monitor would either flicker or give me a blank screen.

So I went on amazon and bought this
1576736337673.png


Still couldn't get it to work.


I'm wondering if my MacBook is defective or if I'm doing something wrong. Please help
 
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Jl006p said:
Thanks for this info brother maybe you can help me out:

I bought this dock at best buy
6357396_sd.jpg;maxHeight=1000;maxWidth=1000

and had to return it b/c DisplayPort wouldn't work. My monitor would either flicker or give me a blank screen.

So I went on amazon and bought this
View attachment 883683

Still couldn't get it to work.


I'm wondering if my MacBook is defective or if I'm doing something wrong. Please help
Click to expand...

That QGeeM cable should be fine. And though it shouldn't matter, any reason why you got it with a female DisplayPort end instead of a DisplayPort plug that goes directly into the display? If none of the USB-C ports work, then try a different cable. Perhaps the DisplayPort cable plugged into the QGeeM cable is too long? Also, what model is your display and make sure it's set to the correct input source.
 
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milhous said:
That QGeeM cable should be fine. And though it shouldn't matter, any reason why you got it with a female DisplayPort end instead of a DisplayPort plug that goes directly into the display? If none of the USB-C ports work, then try a different cable. Perhaps the DisplayPort cable plugged into the QGeeM cable is too long? Also, what model is your display and make sure it's set to the correct input source.
Click to expand...
I got the female one b/c I have a windows gaming pc and I use the DisplayPort cable on both devices. My DP cable is 3 feet. I use a 32" Samsung CHG70 Gaming Monitor. I have also tried doing it on bootcamp. I get an image but the monitor flickers.
 
Jl006p said:
I got the female one b/c I have a windows gaming pc and I use the DisplayPort cable on both devices. My DP cable is 3 feet. I use a 32" Samsung CHG70 Gaming Monitor. I have also tried doing it on bootcamp. I get an image but the monitor flickers.
Click to expand...
It appears you can set the refresh rate on that display to 60 or 144Hz. Have you tried setting it at 60Hz?
 
fishkorp said:
10.15.2 did NOT fix it for me.
Click to expand...
I also have the same problem as you. I have the Caldigit TS3+ and the it does work fine with the screen open. but as soon as you go to clamshell mode it freezes and in about 30 seconds it will reboot. Even rebooting won't help if it stays connected.

I have tried 10.15.2 and 10.15.3 beta and neither have fixed the problem.

Here is a thread that Apple is watching:

They contacted me for more information.

thanks!
Bryce
 
Just adding my datapoint. Using the Caldigit TS3+ with two 4K monitors, 10.15.3 and no issues in clamshell mode or open.
 
ECJ said:
Just adding my datapoint. Using the Caldigit TS3+ with two 4K monitors, 10.15.3 and no issues in clamshell mode or open.
Click to expand...
Are you using the 2019 16 inch MacBook Pro?
I never had any problem with the 2019 15 inch MacBook Pro and a CAL digit TS 3+
 
That's very interesting. I wonder what sets yours different from all of the others. Could you take a screenshot of your MBP display properties (under settings.)
I wonder if there is some sort of conflict going on since the MPB can now select different refresh rates and maybe that screws up the TS3+
 
Just had another issue where waking my machine up caused all of the screens to start flashing on and off, and no amount of unplugging and replugging would fix it. I was able to unplug them all and get the internal display to work so that I could restart, but this is really not acceptable. Sure, waking from sleep seems to work most of the time, but even if it only has a problem once in every twenty times, it's hugely annoying and disruptive. I'm considering just not letting it sleep.
 
bollman said:
I'm not so sure.
I just upgraded from a 2018 15" to a 2019 16". I have a Dell WD15 USB-C dock both at home and at work. I've been using this setup for quite some time with no problem on the 15", but now with the 16", the display flickers. It's like a very quick connect/disconnect once every 5-10 seconds. Totally unusable.
I updated the Dock to the latest firmware but no difference.
Click to expand...
I'm having the exact same issue. With the same setup. I'm thinking the hub just doesn't have enough juice for the 16" and the upgraded graphics card. It works fine connecting my wife's regular MacBook to my Dell monitor.
 
bollman said:
I'm not so sure.
I just upgraded from a 2018 15" to a 2019 16". I have a Dell WD15 USB-C dock both at home and at work. I've been using this setup for quite some time with no problem on the 15", but now with the 16", the display flickers. It's like a very quick connect/disconnect once every 5-10 seconds. Totally unusable.
I updated the Dock to the latest firmware but no difference.
Click to expand...


i have exactly the same issue only with the Caldigit TS3+ dock and also if i connect the screen directly to my MBP 16". Is there any update on a solution yet? I've never had this issue with any of the previous macbooks.

Quite bummed this is happening on a top of the line MBP for this much money.
 
undersmusic said:
i have exactly the same issue only with the Caldigit TS3+ dock and also if i connect the screen directly to my MBP 16". Is there any update on a solution yet? I've never had this issue with any of the previous macbooks.

Quite bummed this is happening on a top of the line MBP for this much money.
Click to expand...
Don't blame the computer, it's the shoddy docks.
 
mightyjabba said:
I blame Catalina more than anything, but if the docks work with other computers and not this one, I’m not sure if it makes sense to blame the docks.
Click to expand...

So I got a replacement machine on Tuesday because of the coil whine issues I've been discussing in another thread, and after restoring my Time Machine backup, the display connected to the Pro Dock was set to 30Hz and couldn't be changed in System Preferences. I disconnected the machine from the dock and zapped the PRAM, which worked for me.

Since I don't know your exact setup, and if I was troubleshooting, I'd also try connecting the power adapter to the machine, as the dock cannot provide a full 96 watts of power the system's rated for. So it's possible the system's underpowered.
 
I’ve got a usb-c to mdp tb3 cable on the way to use an original 4K iMac in target display mode, and if it doesn’t work I’m going to freak the hell out, because this is day 15 since I bought the MBP16, 1 day beyond when I can return it, and I’ve realized I absolutely cannot do any CAD design work on a little Laptop display.
 
ThunderSkunk said:
I’ve got a usb-c to mdp tb3 cable on the way to use an original 4K iMac in target display mode, and if it doesn’t work I’m going to freak the hell out, because this is day 15 since I bought the MBP16, 1 day beyond when I can return it, and I’ve realized I absolutely cannot do any CAD design work on a little Laptop display.
Click to expand...
You can't use target display mode on 4K iMacs
 
I’ve got a Dell FHD monitor that doesn’t wake from sleep with 16” MacBook Pro. I use both displays simultaneously and the mbp display flickers attempting to switch to extended mode. The monitor detects hdmi and says no signal is received via hdmi.
The only solution to get it to work again is to restart mbp.
I also checked the console but didn’t find any crash reports.
“It doesn’t just work”
 
I've been having tons of issues with docks and monitors. I just started using HDMI to USB C cables it's much easier.

I mean if you have the budget the best solution is changing to USB C monitors all the way, it's what I'm trying to do right now
 
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