FPS Drop Between Ue4 and Ue5

I haven’t seen this mentioned here:

Setting screen percentage to 50 (half-res) doubles my performance (~30fps → 60fps) while still keeping it sharp because of the temporal upsampling. It does have more artifacts and is noisier than full-res, but it looks pretty similar and I can run it a 60fps now.

Yes, but for me at least, having Temporal Super Resolution enabled with ScreenPercentage at >80% gives worse performance than turning Temporal Super Resolution off.

So the default of having it enabled and ScreenPercentage at 100 is just throwing performance away.

Look, I don’t want to be that guy, but someone needs to. This is a beta of a game engine that is not planned for release for at least a year still, with not one, but two extremely new technologies that single handedly change the current landscape of realtime graphics.

Why would anyone expect it to offer better, or even the same performance as a release version with technologies that are tested by the community and improved upon for years?

They said in the demo argument… I’m pretty sure they meant the actual release, not the first draft of a public beta (remember, betas are for TESTING and finding problems, not expecting that no problems will exist.)

But if I remove lumen and nanite it’s a prettier UE4. No it’s not. It’s expected to be buggy and also adds a ton of new features like animation and audio.

Disappointed about the new tech being heavy? First off, it’s new tech and it’s beta, aka not optimized, see the paragraphs above. Second, even optimized I highly doubt it’ll have the same or better performance than current and tested and optimized RTR tech. Point is to make it cheaper than hardware rendering through RTX. And I’m pretty sure it already is to a degree, considering it runs (however slow) on hardware that RTX simply can’t.

It’s one thing to report things like those issues, another to expect it to already be optimized. I’d understand those arguments if EPIC was saying it’s safe to transfer over. But they clearly say it’s NOT ready for production.


I notice that my both coolers from gpu working for now, before on ue4 memory from card was not used too much when I drop around 180fps at my project and in this case my VRAM was used as well, now at ue5 it get more memory from gpu instead vram interesting.

Thanks for the intel. For those who say that disabling all of this stuff is basically 4.26, keep in mind that there are new features aside from the rendering stuff.

i can’t change those values. the checkboxes are selected (true) but don’t allow clicking. what should i do?


i figured out i could disable those properties in /Script/Engine.RendererSettings:

  • r.TemporalAA.Upsampling=False
  • r.TemporalAA.Algorithm=False

i’ve made all of the changes you recommended and FPS Drop Between Ue4 and Ue5 - #29 by Greendale_AB too, but my fps is still 3-5fps. i’m using linux but fwiw windows on the same hardware runs fast and smooth. system specs in my about me if you click on my avatar

does anyone have other ideas for fixing perf?

[edit 2]

i updated the nvidia driver to the latest available (460.73.01) and with none of the performance settings changes above, meaning default project settings, the fps is back to fast and smooth! it also fixed the visual quirk in this pic.

I’m not using Linux, or in the first place have UE5 installed at the moment. I need to free up some space for it first, plus my laptop is far lower than minimum specs for the demo.

I just wanted to ask, is there any official statement about the state of UE5 on Linux? Maybe it’s not yet compatible, even if it can be built for it? I honestly don’t know and haven’t seen anything one way or the other, but your system specs should handle way above 3-5 fps. Especially with the changes you made.

Considering you mentioned that on the same system on windows it runs well, maybe it’s a temporary OS incompatibility?

ya linux is obviously not a tier 1 platform for epic so it makes sense it lags in perf and optimization will come later.

such a big drop that makes it unusable for continuing to learn is what i’m trying to find a workaround for because i have good momentum going and i’m having fun.

other related topics i’ve started are Ue5 game dev on linux? and Understanding how linux fits in



Lol are you completely daft?
Rendering at 50% the size obviously renders 50% faster.

Surely you can’t be serious… XD

i also faced a problem of 120 FPS in UE4 and then 50 to 60 FPS i UE5

yeah bro i was have around 160 to 180 FPS in UE 4.26.2 and in UE 5 i am have max of 60 FPS

Yes, I’m serous. Epic intends to use temporal upscaling (which is why I mentioned it):

Temporal Super Resolution has the following properties:

  • Output approaching the quality of native 4k renders at input resolutions as low as 1080p, allowing for both higher framerates and better rendering fidelity.

Lumen relies heavily on Unreal Engine 4’s Temporal Upsampling with the new UE5 Temporal Super Resolution algorithm for 4k output.

For comparison purposes, the following GPU timings were taken from the PlayStation 5 Unreal Engine 5 technical demo Lumen in the Land of Nanite:

  • Average render resolution of 1400p temporally upsampled to 4K.

That fixed it for me :smiley: thanks

Ram is focused mainly on as someone pointed out loading things into memory. Also, it’s about textures. If you have a bunch of 4k textures, you’re going to reach your streaming pool size limit. A lot of people say more ram isn’t always better. While yes, that is true in some cases. 64-124 Gb of ram doesn’t hurt. There are QUIXEL game dev’s who max out their ram. It’s more though in good practice to optimize your texture sizes. For me, foliage isn’t something someone is going to crouch down and stare at, so I lower my foliage texture sizes. Optimize your game to focus on things the player is going to pay the most attention to.



i7 8700
16 go ram
gtx 1060 6gb

Third person template nothing more
Same screen, same resolution, no content browser
The ue5 viewport is even a little smaller due to the UI

Listen server, only one client, two screen

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with all these changes my scene is still down from 34~fps to 23~fps, with the cost of my basepass more than doubled!! im really struggling to work out what’s up here, something seems super wrong, to be fair its a very foliage dense scene but hopefully this performance drop isn’t something that hangs around when UE5 releases

My results are different!
In UE4 I could only place static mesh with 15 million vertex before before performace dropped to 30 ms. On UE5 with 50 million vertex its 16 ms, without any nanite. With 96 skinned mesh running around in a scene (crowd-humans, 40,000 vertex each, 4 animations) I get 17 ms.

I am yet try UE5 on production system and important projects as they don’t recommend it. Test system vulkan-linux 1050ti

Try this : Tip to get better fps on UE5

I don’t know too much about UE5 and do not doubt some users are experiencing frame rate issues. Everyone’s experience will differ according to their computer specs and the scene being rendered.

However, rather than convert a UE4 project, I created a new project in UE5 with any empty level (not blank - totally empty). I then created the simple scene in the image below from scratch. The scene renders at an acceptable frame rate of almost 60 FPS bearing in mind that it:

(a) uses the default UE5 settings (including the Lumen settings); and
(b) is running on a 4 year old laptop with modest specs - i7-9750H CPU (6 cores/2.6 GHz), GTX 1650 GPU and 32 GB RAM.

So really, not too shabby given this is an early release of UE5 which has yet to be optimized. I’m guessing, but importing an existing UE4 project with its own hairs and pimples may one of the reasons users are seeing mixed results.

the issue isn’t so much that in a vacuum UE5 runs bad, but i’d be interested if you recreated the exact same scene in UE4 how it compares, and also, in my simpler scenes they are a lot closer, but in scenes where GPU cost is higher in either engine, it performs much worse in UE5 is my real issue