Internal video acceleration for games is supported only under macOS 10.14+.
If you are using macOS 10.14.6+, you can accelerate applications and games with the eGPU if they support GPU acceleration...
• Select the app in Finder
• Get Info
• Select Prefer External GPU
To get the maximum game acceleration, connect a game display to external graphics.
The Opticis DPAX DisplayPort 1.2 Data Recovery Repeater is an active repeater for DisplayPort video signals, increasing video transmission of a DisplayPort signal up to a combined length of 18m:
Locate repeater up to 3m (10ft) from the Source and up to 15m (49ft) to the Display at DP1.2.
DPAX complies with DisplayPort 1.2 standards and supports Ultra High Definition (up to 4096x2160) at 60Hz.
