[SOLVED!] Stuttering on an empty project on both Mac and Windows

Development Getting Started & Setup
1

Hello everyone,

I’ve just installed UE 5.4.3 in both an iMac and a PC. These are the specs:

  • PC: AMD Ryzen 5 5600X 32,0 GB of RAM NVIDIA RTX 3070 ti. Windows 11 Pro 64 bit.
  • iMac 2017: i7 16 GB RAM AMD Radeon Pro 580. Ventura 13.6.3.

In the PC I’m getting around 100 fps but the movement is not smooth. I’m getting some sort of micro-stuttering. It is not extremely obvious, as you will see in the following video, but it’s there and it’s very annoying. Bear in mind that I don’t have this issue in games made in UE, like Hellblade.

Video: Watch UE Stuttering PC | Streamable

In the iMac I’m getting around 30 fps but the stutter is horrible, as shown in these videos:

Although the level of stuttering is considerably worse in the iMac, maybe they are caused by the same thing.

These are the things I’ve tried:

  • Disabling UDP Transport, both the option and the plugin entirely.
  • Disabling Studio Telemetry plugin.
  • Disabling High DPI Support.
  • Disabling "Display viewports’ at high DPI.
  • Disabling antialiasing.

All I have achieved with some of these settings is improving the framerate a bit but the stutter is still there in both platforms.

Any idea of what could be causing this issue?

Thank you for your help :pray:

2

I have great news! I’ve been messing around with “Engine Scalability Settings” in both PC and mac, and there seems to be a problem with the settings “Global Illumination” and “Effects” (and especially this second option). Let me explain:

On my PC, I can put all settings on “Cinematic” and it works fine (no stutters) until I put “Effects” on any setting higher than “Medium”. As soon as I do that, I start getting stuttering again. But, even if I put “Effects” back on “Medium”, the stutter persists until I put “Global Illumination” also on medium. Very strange.

So right now, on my PC I’m getting 120 FPS (no stutters) with these settings:

image
image1627×1386 133 KB

And on the iMac I’m using a very similar configuration.

I’m so glad I found the issue :smile::pray:

1 Like
3

I have the same (or at least very similar) problem. Even on a blank project, I’m experiencing regular stuttering (“chugginess”) around 2-3 times per second, which only goes away when switching “Global Illumination” to low/medium.

Even if I force a LOW fixed framerate, the lag still occurs every X frames.

What’s interesting is, this is not absolute. Sometimes Global Illumination will be on highest settings and the game is smooth. Then suddenly randomly out of nowhere it starts chugging again until I set it back to low.

Here’s a video clip which clearly shows the problem: https://youtu.be/u2Mr2mkvUcI

I don’t recall/can’t seem to reproduce the problem in UE5.3.2, it only appears to be in 5.4.x (I’m on 5.4.4)

so it seems to me like this is still an issue that shouldn’t be marked as SOLVED?