This is far from resolved. Just had to switch back to a 1080p monitor because my 4k had a technical issue. And just like that AE runs like a charm. This is pathetic. It's a crawl on 4k and up. Im running a 11900k with 64GB dedotated wam. How can the dev team ignore this blatant ****-up and thousands of comments pointing it out?

Not resolved even in the 2023 version. This is a huge problem.

Not resolved.

This problem has been happening to me ever since I upgraded to an LG ultra wide 5K x 2K monitor. I have tried everything, different graphics drivers, uninstalled programs and even reformatted the C drive and nothing fixes this. I have been able to test on 3 completely different high end computers and they all have the same problem. After Effects also makes Cinema 4D/ Redshift crash at high resolution too.
If I keep the resolution at 1920x1080 then everything is fine but as soon as I go above that it gets worse the larger the resolution is. Also, scaling down the AE window on the 5K display improves the performance but this is no work around.

This should be fixed by now Adobe! What are we paying for? I don't want multi CPU rendering if I can't go above 1080p resolution...

I have the same problem here. I'm working on Asus 4k monitor MG28U and it's very laggy with After Effects.
Can someone tell me if this problem occurs on 2K monitor as well ? Because I'm planning to buy a new one.

Not solved June 2021. Come on Adobe sort it out.

why you still have this issue from 2018 to 2021, what did you do in 4 ******* years?

This is still an issue! Please fix it :(

I have this issue too using a 2018 Macbook pro with a 4K Benq monitor. I've found a workaround is to change the Display Resolution to 'Default for display' in system preferences. Everything in the UI is massive now but at least I can play back in real time. And my AE is up to date (17.5.1)

This issue still has not been fixed. AE runs like trash on a 4K monitor once you have a somewhat heavy project open. Only way to kind of fix the issue is to enable DPI scaling override in compatibility settings, but that, of course, makes the UI blurry, so what is the point of having a 4K monitor then? It is absolutely bizarre that it is 2020 and 4K monitors have been around for years and Adobe still hasn't fixed this ****. I don't think they are even aware of it. What are we paying for?

This issue is not resolved. I'm having this problem with AE CC 2019 and 2020 on Windows with a 4K display. The only fix that works for me seems to be turning scaling off, but then the UI is so small it's unusable, so that's not a solution.

*Edit - Now I have had a chance to try this on a Mac Book Pro external to 4k display, and the same issue persists. The only way to get realtime playback is to set the scaling in Mac OS X to "Larger Text, Looks like 1920 x 1080" but that makes the UI way too huge and negates the benefits of having 4k! I have experienced this issue now on Windows and Mac while connecting to an external 4k display. Please look into this, it is very frustrating and is a basic function of your software that should work correctly.

I'm having the same problems as everyone here. Running the latest version of AE on the latest 2019 MacBook Pro (top spec) and Dell 4K monitor.

When is this going to be fixed?

This is not solved at all.

This is such a huge issue. Both Premiere Pro and After Effects run like garbage on a high-DPI display. On my iMac Pro, both have to be run with "Open in low resolution" turned on for both apps. This is the latest release, and every release prior. Like everyone else said, the only other option is to just shrink the window side down to 1/2 or 1/4 of its size. Ridiculous!

This shouldn't be marked as resolved, the November 2019 release did nothing to resolve this issue. If anything, it seems to have made things worse.

The problem still exists in AE 2020. I just installed it and had a quick test with VideoCopilot Element 3D. The performance is directly dependent on the comp viewer size, not on the render resolution. I made a UHD comp and set the render resolution fixed to quater: When I make the comp viewer small (or the app window) it runs smooth as butter. When I make it large it becomes a slide show. This is frustrating.

Windows 10
128 GB RAM
NVIDIA RTX2080 TI
LG UHD Display

I've just installed the 2020 version of After Effects and I was hoping to see some performance improvements but I'm sad to say there are none. I'm using AE on a 4K monitor and on big projects the UI is still slow and sluggish and just completely unusable. And yes, I know, changing the DPI settings improves the performance, but it also makes the whole UI blurry and honestly who wants to have blurry UI on a 4K screen? The whole purpose of a 4K screen is to have a crisp, clear, beautiful picture in front of you.

Adobe is great when it comes to releasing new and fancy features, but when it comes to actual performance improvements they couldn't care less if I'm being honest.

The whole UI in AfterEffects and Premiere is rendered using one single CPU thread. Which is not enough on high DPI monitors. Once that core is fully used, it throttles everything down, even the playback. I happen to work on a i9-9900K, so it could be worse. I'm looking forward to GPU-accelerated UI rendering or at least multi-core supported UI rendering in the CC 2020 update. Thanks in advance!

I'm having the same issue. I've resorted to using the 'hack' described below which gives a After Effects a blurry UI. Very disappointing.

Hey folks,

Until a fix is in place, a really good workaround for this is to:

1) Find AfterFX.exe (usually somewhere like "C:\Program Files\Adobe\Adobe After Effects CC [whatever]\Support Files\").

2) Right-click, and open up its Properties.

3) Click on the Compatibility tab

4) Click on "Change high DPI settings".

5) In the new dialog box, tick "Override high DPI scaling behaviour".

6) Change "Scaling performed by:" to System.

7) Hit OK, and Apply.

Now, load up AE, and all of a sudden you have proper playback. The UI doesn't look as crisp anymore, but that's all. In terms of being able to do the job, or not do the job, it absolutely works in the interim.