Macbook Pro late 2016 and 4k monitor Dell P2415Q input lag only @ HiDPI scaling
 

Hi,

I'm user of Apple MacBook Pro late 2016. Spec:
- Intel Core i5 2 GHz
- 16 GB
- Intel Iris Graphics 540 1536 MB
- Mojave 10.14.1 (18B75)

Today I bought external UHD 4K monitor Dell P2415Q (3840px x 2160px). I've connected it via Displayport. It works fine on its nominal resolution (@60Hz) (which is of course unusable, everything is too small), but it gets problematic when it comes to scaling.

First weird thing I noticed that I have both 1080p and 1920x1080 on the list which as I assume are both the same. Anyway:

- 1080p@60hz looks blurry and lowfi
- 1920x1080@60hz has gui/input lag which is most visible when moving mouse cursor (It jams every few seconds), but it lags overall (video, typing, gui animations, etc)

I've noticed that even if monitor is connected, when I move mouse to the builtin macbook's display, it starts to move fine and smooth. Even if there is video played on Dell's monitor. And even if I connect my old AOC Full HD external monitor.
With 2 displays connected mouse jamming and gui lag is visible only on Dell and only on that HiDPi scalling resolution. Everything on others screens works smooth and fine.

It didn't help when I plugged out AOC and went to closed clamshell mode. It's strange to me, because I've never experienced lag on my macbook pro and I've never had a problem with scaling on builtin display.

It occurs only on HiDPi resolutions. Funny thing is that it works fine on 2560x1440, but lagging on HiDPi 1280x770 which is actually the same resolution but with gui scalling.

My first idea was lack of graphic card power. But if so why everything works fine when all displays are connected. I can notice lag only on Dell. Moreover, I have Microsoft Windows 10 installed as a second system using Bootcamp and I'm not experienced lag on it.

I've DisplayLinkDriver 5.0 (42) installed. Dock station is i-tec USB 3.0/USB-C with DisplayLink DL6950 chipset.

Video of the problem (first I'm showing Dell and then Macbook's display): https://drive.google.com/file/d/1-GL...ew?usp=sharing

Please help guys.

https://discussions.apple.com/servle...5+18-11-12.png

Update:

I've connected Dell through DisplayPort <-> USB-C cable omitting I-TEC and issue is no longer visible :cool:

So, in summary:
- :mad: DisplayLink & MacOS Mojave 10.14.1 = lag, jamming & smoothness drops
- :) DisplayLink & Windows 10 = everything OK
- :) NO DOCK STATION & MacOS Mojave 10.14.1 = everything OK

It's obvious that there is something wrong with station. Moreover, it seems that it's specifically related with macOS drivers.

I've found that when I plug in Station, it spams Console.app with one line:


WindowServer [ERROR] - Unable to find display pipe for IOFB service: 18715
WindowServer [ERROR] - Unable to find display pipe for IOFB service: 18715
WindowServer [ERROR] - Unable to find display pipe for IOFB service: 18715
WindowServer [ERROR] - Unable to find display pipe for IOFB service: 18715
WindowServer [ERROR] - Unable to find display pipe for IOFB service: 18715
WindowServer [ERROR] - Unable to find display pipe for IOFB service: 18715
(...)

Maybe that can be the clue.

Does somebody know how to fix it?

Can you give me any update (actually any answer)? Do you work on issue, did you find a solution? Did you decide to not fix it? Is it os related and can't be fixed right now?

Don't get me wrong, but I post this thread few month ago and you (and by you I mean any official DL member) didn't give a single reply.

Getting the same error on top of other errors. Screen freezes every couple of minutes, no solution in sight.

same here
 

Boatloads of [ERROR] - Unable to find display pipe for IOFB service: 19223, laggy in all windows with a scroll in them. Tried to uninstall/reinstall and different ports on my https://www.wavlink.com/en_us/product/UG69DK1.html

Running 5.1.32 driver version on Mojave 10.14.3 on a 15" MacBook Pro 2016

I have the same problem on Mojave 10.14.3 with DL-6950 and 4k screen. Native 4k resolution works fine, but it is too small. Scaled HiDPI resolutions are very choppy. I could live with native resolutions only, but these random freezes are really a problem.

same here
 

2016 macbook pro, 10.14.4
no problem on 4k non-hidpi, 60Hz, but very laggy on hidpi

Same here
 

:mad::mad::mad::mad::mad:macbook pro 2018 , It's been over a year and their products are still on sale, but the problem remains unsolved and they are not responsible for their products。

same issues
 

I spent a lot of time doing the same tests as you, and the conclusions are the same as yours. However, the problem still exists in 2020.They do not seem to be addressing the issue or are unable to resolve it. I hope to get a reply. I am very disappointed.