I have a roughly four-year-old HP laptop running Ubuntu. It has one HDMI port, two regular USB ports, and a USB-C port that supports data only—not video output or DisplayPort Alt Mode. I need to connect two 4K monitors at 60 Hz. What hardware or setup can provide the second display, and what limitations should I expect?
2 Answers
Look for an adapter based on a DisplayLink chipset such as the DL-6950, and plug it into a regular USB 3 port. It may support 4K at 60 Hz on paper, but actual results depend on the laptop, USB bandwidth, driver, and monitor connection. It should be fine for office work, browsing, and video, but it is not ideal for gaming or other graphics-heavy tasks because the CPU has to help encode the display stream. Some models advertised for Windows do not have usable Linux support, so verify Ubuntu compatibility first.
Use the built-in HDMI port for one monitor, then connect a USB 3 DisplayLink adapter or dock for the second. DisplayLink adapters contain their own graphics hardware, so they can output video even when the laptop’s USB-C port does not support video. On Ubuntu, you’ll need a compatible DisplayLink/Evdi driver, and Linux support varies by adapter, so check the exact chipset and current driver compatibility before buying.
Will a DisplayLink adapter reliably reach 4K at 60 Hz on Ubuntu, or should I expect noticeable lag?
A dock with DisplayLink can simplify the cabling, but it has the same driver and performance limitations as a standalone adapter.