Very strange FPS issue - editor vs standalone vs packaged

I’ve been tearing my hair out all week with a project that seems to have half the FPS in the final packaged (shipping) build (or standalone editor build) compared to just in the editor @ fullscreen.

Literally tried every suggestion I could find online, eg vsync, Engine Scalability Settings>Monitor Editor Performance off, resolutions, screen percentages, config additions, disabling smooth framerate, SceneRenderTargetResizeMethod, disabling gsync, everything.

Today I have realized the exact same issue happens in a brand new UE5 third person project too! Default and untouched. So I’m hoping this is a breakthrough and someone could help.

Here is the third person UE5 template project running in fullscreen editor

Here is the same in a standalone editor preview at fullscreen

Here is the same in a fully packaged build (with editor closed)

Really grateful for any insight anyone can give as this problem is killing me :sleepy:. I am using a RTX 2080 TI with a i9-9900k running at 144hz. 32gb ram Unreal Engine 5.0.3

Update: The issue remains in the untouched 3rd person project when turning off lumen and virtual shadow maps. I’ve also checked the default project settings and smooth framerate and vsync are already off by default.


So, I just posted this a couple days ago. We are probably on our own with this:

In addition to the discrepancies, I have watched about 5 hours of video tutorial, read around 10 articles, scoured the documentation… and cannot explain any of this and nothing seems to work.

Fortunately, my current performance is satisfactory; but not on potatoes. From what I’ve learned, your problem seems very similar to mine: your Frame time sucks and I can almost guarantee your FEngineLoop is also taking a very long time as well.

We cannot see what is happening during this time for these events. I’ve found as much info as I could on these, but I think without actually profiling the source directly with our own code, we are never going to find out more. I certainly don’t have time to do that, unfortunately. Then in addition, most likely, it will be engine level changes to get this to be addressed.

It’s unfortunate all around.