MBP 16" and External Display Stutter

[Michael_10]

Hello,

Looking for some advice and to see if anyone else has ran into this problem. Connected my new MacBook Pro 16" to an old LG 23MP65 IPS 1080P monitor via a USBC/HDMI cable (the cable is rated for 4K@60FPS).

When the display is running either as a mirror or extended, every 4-5 seconds there is a stuttering on the display, almost like it skips a frame, the best way to describe it is if you are making a circle with the cursor it sticks or jumps every few seconds.

I have bootcamp installed but the issues doesn't seem to exist when running Windows. Anyone else had a similar issue or suggest anything that could be changed in settings? I have stopped macOS from switching to the iGPU and forced it to use the 5400M but this hasn't made a difference.

Thanks!

 

[Alpherah]

Random question - if you make a New admin user does the issue persist ?

 

[GMac11]

Could be worth checking the refresh rate in the display settings within MacOS? There are usually a few settings, just in case it's at 30hz or something.

 

[Michael_10]

Issue persists with another account on MacOS, and I've got refresh rate set at 60Hz in settings. Are there any updates or AMD programs I should install for the discrete GPU? I am wondering if there is a problem with the way it is handling the external GPU. I know on my Windows install there is the Radeon Control Panel that is installed.

 

[Alpherah]

Have you tried connecting to any other external display (just a tv will do) to see if the issue persists? If it’s an old display whilst it should be fine we can’t rule out there being something Mac OS doesn’t like about it

 

[Michael_10]

Have you tried connecting to any other external display (just a tv will do) to see if the issue persists? If it’s an old display whilst it should be fine we can’t rule out there being something Mac OS doesn’t like about it

no issues with my TV. Looks like it could be a monitor issue. Strange it doesn’t replicate in Windows. Any chance a USB C to DisplayPort could eliminate the issue?

 

[GMac11]

I was going to say USB C to DisplayPort is the only proper way to run an external display from a MacBook IMO - but I don't know if your monitor has a DP input so wasn't sure how useful that suggestion would have been. I can run my MacBook on my Acer 35 at 1440p 120hz and it looks great.

 

[Michael_10]

Sorry typo there on my part, it's a DVI port the monitor has, not a DisplayPort.

 

[Alpherah]

no issues with my TV. Looks like it could be a monitor issue. Strange it doesn’t replicate in Windows. Any chance a USB C to DisplayPort could eliminate the issue?

I would use an adapter rather then an all in one cable from my experience at work, but it’s another expense if it doesn’t work

 

[Spit]

I use mine all the time with a Samsung 4K Q60 and it runs 4K/60 buttery smooth.

You say it’s an old display so maybe it’s that?

 

[Michael_10]

I use mine all the time with a Samsung 4K Q60 and it runs 4K/60 buttery smooth.

You say it’s an old display so maybe it’s that?

Quite possibly, why though the issue isn't there in Windows I'm not sure.

I have ordered a USB C hub with an HDMI port to see if this improves the situation. In the future I am planning to get a new monitor anyway. Until then I might have to get use to the stuttering!

 

[Alpherah]

This issue is quite prevalent on windows machines actually - but resolvable via some settings tweaking.
Obviously for better or worse not possible on Mac OS

 

[Michael_10]

Some good news, bought a fairly inexpensive USB C hub with a HDMI port, connected an HDMI cable and all is working! No stuttering. A very strange bug that I can't say why it happened but good to have the issue resolved, thanks all for suggestions

 

[Alpherah]

Good result!