lower FPS on better machine?

Graphics Shaders & Materials
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1

9410867--1317857--upload_2023-10-15_16-25-13.png
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Screenshot above is on a Ryzen 5 5600x and a GTX 1650 Windows 10

Screenshot above is on a Ryzen 7 2700X and a GTX 1070 Windows 10

Both games are the exact same settings. Both Unity versions are 2021.2.10f1.
This also happens when building, not exclusive to the editor. We have tried messing with build, quality, player settings with no success.

How is this possible? Why does the better GPU have worse rendering in general?

2

The GTX 1070 is a fair bit faster than the GTX 1650, but the 2700X is a fair bit slower than the 5600X. What’s the profiler show for the CPU usage of both instances?

3

The profiler for the 2700X is very weird. It has more overload (4ms more?) and is not consistent.

Below you can see a screenshot of the profiler for the 5600X
9410879--1317860--upload_2023-10-15_16-42-18.png
Versus the 2700X
9410879--1317863--upload_2023-10-15_16-42-31.png

On some other occasion the 2700X looked like this:
9410879--1317866--upload_2023-10-15_16-43-20.png

We also tested this on empty scenes, the 5600X gets 1000FPS 0ms CPU while the 2700X gets 300FPS with 4ms CPU time

4

The question is, can the worse CPU bottleneck the GPU this hard? On build, both computers didn’t use over 30% of the CPU/GPU which is very confusing to me.

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GPU here is at 100% because I turned Vsync off

Notice how the 1070 is capped at 50% on the 2700X machine… all while getting low FPS? And with 35% CPU usage? Why is this happening?

5

Yes. Unity is mostly single threaded. The 2700X has more cores and threads but the 5600X is about 50% faster per thread than the 2700X. That’s roughly the difference you’re seeing in the frame rate too. A 50% increase to 40 FPS is 60 FPS.

Task Manager is deceptive with its percentages. It won’t show 100% total usage if the apps running aren’t capable of using all the cores and threads of the CPU. It showing 35% total usage means that the apps running are using about 1/3rd of the cores and threads which aligns with what the graphs show.

6

quick update on this: I fixed it by batching my materials together using Mesh Baker. The low performance was due to too many draw calls.
and also apparently the 5600X is really good at sending draw calls