I'm using v2020.3.4 with URP 10.4.0 2D Renderer, and vsync off. If I choose OpenGLCore in the Project Settings, I get 20 FPS, for example. If I choose DirectX, I get 40 FPS, the double. I've check the profiler and the main difference is that when using OpenGL, there is an entry in the CPU Usage called "Gfx.WaitForPresentOnGfxThread". I remark: vsync is off. This entry appears every N frames, consuming 21 ms. Here you can see the profile when using DirectX: And here when using OpenGLCore, at the frame where the suspicious entry appears: Is this an expected behaviour or a known issue? Why does it happen?