Poor performance on MacBook Pro external display, not on native

Hello,

I used to play D3 a lot on my MBP, at reasonably high details and reasonably high resolution (over 2000 x whatever) with reasonable good performance (~40 FPS).

I recently purchased a 4k monitor that I used by itself (meaning I have external keyboard and mouse and the laptop is closed so only the external screen is used) connected to the Mac through USB-C and the performance is clearly insufficient (gets acceptable at ~1600x1200 with low graphics and even then it is not smooth).

I would understand if the performance were consistent between the two setups, but here the difference is weird.

Any opinion? (except running Windows :D).

https ://d.pr/i/qCvgGB

https ://d.pr/i/xq214V

Hi tisek

That falls a bit outside what we can support here on the Technical Support forums, but it sounds like using an external monitor over USB-C is defaulting to the integrated graphics card, instead of your discrete one. That’d explain the large performance difference, too

That’d be where I’d start in looking into troubleshooting at least, and hopefully that sets you on the right path towards finding a solution