Plugable tops our list of best thunderbolt docks for your laptop precisely because the company focuses on the most important element: display connectivity, with two 4K displays. But at CES, the company improved its game: now there are three!
The $ 219 Pluggable UD-6950PDZ includes support for three 4K monitors, not just two. And in the spirit of plugable docks, the company doesn’t let you choose between DisplayPort and HDMI connections: the UD-6950PDZ includes three of both.
The dock works with a standard USB-C port on your laptop, but you need an available Thunderbolt port (preferred with Thunderbolt 4) to take full advantage. Unfortunately, the dock’s specifications hide some pitfalls and answer the question of whether a Thunderbolt dock can hold three 4K displays. The answer? More or less.
In particular, the UD-6950PDZ has a pair of DisplayPort 1.2 / HDMI 2.0 ports on the rear that can output 3840 × 2160 video at 60 Hz – the 4K60 output expected from Thunderbolt docks. But the third port is HDMI 1.4 / DisplayPort 2.0 and is instead limited to a resolution of 3840 × 2160 at 30 Hz. To be fair, 30Hz is acceptable for a secondary display used for static content like email or messaging apps, but stare at a 30Hz display for long periods of time can strain your eyes.
But there is another pitfall. None of the 60 Hz DisplayPort / HDMI connections support HDCP, which means that protected content (a Blu-ray Disc or Netflix or Amazon Prime) can actually be displayed on the screen. Instead, HDCP is listed as “host dependent” on the 30 Hz port. Simply put, you’re trading in a third display for frame rate limits and a general limitation on HDCP playback. (To be fair, you can almost certainly play protected content on the laptop itself.)
Otherwise, there is a lot to like about the UDZ-6950PDZ. The Thunderbolt connection back to the host can support 60W of power and cover a wide range of mainstream and thin-and-light devices. The dock also supports six USB-A ports (all 5 Gbps, two on the front and four on the rear). If there’s another weakness it’s that it doesn’t have a USB-C output of any kind so you can’t add an additional one USB-C dongle if, for example, you suddenly need an SD card slot.
Plugable will ship the dock later this quarter, Plugable said.
As Managing Editor of PCWorld, Mark’s focus is on Microsoft news and chip technology, among other things. He has previously written for PCMag, BYTE, Slashdot, eWEEK and ReadWrite.