I have iMac 5k which has onboard Radeon pro 580 and can get very good fps 40-50 with quality High(hdr), FXAA, objects medium & reflections low. But I decided to get e-gpu Sonnet (550w) and Radeon Vega 54 connected to external monitor as useing for UHD video work. Issue is I follow your instructions I have set application to use external GPU as per Apples instructions launch XP11 and under settings it still see’s onboard gpu as primary monitor and the external as monitor 1, so I updated settings to not use primary and to only use monitor 1 but I get terrible fps no better than 20fps. Running external benchmarks and the Vega 54 is averaging over 120fps @1440p & can also see final cut when I select use external gpu it does just that. So is there something that also needs modifying for XP11 to work properly with e-gpu?