DisplayLink and some other USB and wireless displays no longer work on macOS 10.13.4 Learn More.

USB Graphics Performance Tuning

Performance Tuning

A USB graphics adapter is a “virtual” device that uses your machine’s CPU and memory to render graphics. It then transfers just the pixels that change over the USB 2.0 cable to the device. The screen itself is refreshed continually (60 times a second) by hardware over the monitor’s own cable, from memory on the device.

  • When nothing on a USB screen is changing, the PC is doing little or no work and nothing is going over USB. Meanwhile, the screen continues to refresh directly from the device.
  • However, when most pixels on the screen is changing, your CPU is doing the heavy lifting, and also the (480Mbs) USB 2.0 bus can become a bottleneck. You may start to notice lags in mouse or window movements.

If you’re experiencing slowness or latency on your USB display:

  • Reduce your screen resolution with the operating system display control panel.
  • Play 3D games and videos on your primary (non-USB) screen.

By reducing the amount of data that needs to be compressed and sent over USB, you’ll increase responsiveness.