RE: Dual U2417H, MST doesn't work when using an AMD R5 430, CentOS Linux 7.4
Unfortunately, you are in non-tested waters. Dell never validated/tested the U2417H in Linux. We only validated/tested for Windows 7/8/8.1/10. The U2417H hardware is DisplayPort 1.2/MST daisychain capable, but you are at the mercy of the Linux AMD drivers as to whether they can activate the DisplayPort 1.2/MST daisychain. If not, each U2417H will need to be connected to their own port on the AMD video card. You should ask the Linux users here.
But why in the first place? There is no performance increase by doing MST? On any U2417H in-port DP/mDP/HDMI, the U2417H will only do 1920x1080 60Hz. So by connecting them to different video card ports should not matter?
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