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Fixed in 2022.2.X

Duplicate in 2020.3.X



Found in

Issue ID




[Apple silicon][M1] Game view FPS is very low when the view is moved to an external display



Using an external display on an Apple silicon MacBook Pro laptop causes playmode FPS to drop significantly.

1) Connect an external display to an Apple silicon-based MacBook Pro
2) Create an empty project. Make sure the scene view is not visible but the game view is. There's another, separate perf issue when showing both at the same time.
3) Enable the "Stats" button in the game view.
4) Enter play mode.
5) Move the game view between the built-in display and the external display. Leave it for a few seconds each time to let FPS stabilize. Note the values.

Result: Performance on the external display is very poor compared to the internal display
Expected: Much better performance on external displays

Comments (21)

  1. unity_skPGxJ5XjTl8yw

    Mar 18, 2022 22:00

    Same here, unity 2021.2.16; 32 GPU cores and 64GB Ram

  2. unity_skPGxJ5XjTl8yw

    Mar 18, 2022 22:00

    Oh yeah, SAME HERE!

  3. toyhunter

    Mar 05, 2022 15:23

    Additional finding: A blank screen run 500fps in MBP monitor, drop to 80fps when moving the Game play window to external monitor.

  4. toyhunter

    Mar 05, 2022 15:21

    Same here! Using M1 Max base model with LG ultra-wide monitor, fps drop almost 50% when using external monitor than using native MBP monitor.
    Unity please fix it.

  5. mitchmunro

    Mar 04, 2022 23:19

    This issue makes development on unity very painful - as development has to be done on the small 14" screen, and even sometime that doesn't fix it.

    The issue always comes when I use the play screen on the built in monitor, and sometimes come up when I use the play screen on the built in monitor too.

    Using Macbook Pro 14" 2021, M1 Max, 24 Core GPU, 32GB Memory, running Monterey 12.1, and using Unity 2021.2.9f1.

  6. cocopixel

    Feb 19, 2022 01:27

    same here

    - unity 2021.2.10f1
    - m1 pro
    - lg ultrafine

  7. unitydev112

    Jan 30, 2022 08:36

    Same issue...
    I have an assumption, that the fps is just .5 * (hz of display). Does this make sense?
    I only tried with my 60Hz Display => 30fps; configuring the display to 30Hz => 15fps.
    Can anyone confirm this? (eg. 120Hz => 60fps)

    So maybe a bug with forced VSync Count = Every Second V Blank?

  8. eiketre

    Jan 22, 2022 11:50

    Editor works fine, but when playing the games lags a lot. Unable to use it.
    Happens without external monitor too.
    MacBook Pro m1, 16mb

  9. jeremias-volker

    Jan 20, 2022 15:30

    Same here.

    Unity 2020.3.24.f1
    M1 Max (maxed out. 64GB RAM etc.)
    macOS 12.1
    Dell U2720Q via USB-C

  10. jipiboily

    Jan 19, 2022 02:27

    Same issue with latest MacOS, on an M1 Macbook Pro (maxed out), Unity 2021.2.7f1 and an external monitor plugged in through a USC-c hub.

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