Why does my engine stutter after a year with no hitches?

HasTruth · July 25, 2025, 1:16pm

I’ve been developing my first game for about a year now and haven’t had any major issues with editor functionality. My PC broke recently though and had to replace the RAM to fix it (also replaced mobo and ssd). Also had to reinstall windows 11. Ever since then Unreal has been very laggy/stuttery overall.

This means the editor is just as laggy as when I preview the game for testing purposes. It’s laggy when working on event graphs, suttery while moving around the level in the editor… just everything is laggy. I tried so many things to fix the issue to no avail.

Here are some fixes I tried:

Reinstalling UE
Downloading a different engine version
Opening a new project file
Running it on different drives
Disabling telemetry and UDP plugins
Uninstalling and reinstalling GPU drivers and chipset
Updating BIOS

Here are some screenshots.

Specs:
AMD Radeon RX 6700XT 12GB VRAM (ASRock)
Ryzen 7 3800X 8-Core
B550 Gaming X V2 Motherboard
16GB RAM
800W PSU

Do I need to replace my CPU as well? It’s strange that it’s telling me it’s not good enough when I’ve been working with Unreal for a year now without problems. I can also play games on this rig just fine, for the most part. Occasionally I’ll get stuttering in certain games after idling for too long or randomly.

HasTruth · August 6, 2025, 2:02am

After replacing the RAM then later the CPU on my PC, Unreal runs smooth as butter!

Initially I thought my CPU was fine because I could play performance-heavy games on it still. After launching Zen in tandem with Unreal and seeing that there was an issue with not enough cores being used, I tried every possible software-side solution. As I tried everything without success, I decided to upgrade my CPU.

Afterwards, I tried to reinstall the old RAM sticks as extra memory in case they weren’t the problem, but turns out they were damaged after all. PC wouldn’t start with them installed.

In short, if you’ve tried every software-side solution and nothing fixes in-engine stuttering, run Unreal Insights. If the tool tells you there are “not enough cores” on your CPU that seems fine otherwise, it’s likely faulty. If it gives you warning signs for RAM too, replace it as well.