Benson LeungComing to Chrome OS M102: Newer Chromebooks (11th Gen Intel or newer) will notify you if the USB-C cable you're using with a dock or a monitor does not support DisplayPort!
It probably has happened to even the most tech-savvy of us: Grab a USB-C cable we have around to connect our computer's USB-C to the dock's or monitor, but the display does not work. Turns out, it's the wrong cable; a USB 2.0 cable simply doesn't have enough wires.
USB-C and DP Alt Mode have been used on computers to do one-cable display docking since 2015, but as I covered, many USB-C cables look identical but function differently.
Good quality cables certified by USB-IF may have these official logos. These help distinguish cables visually. Logos are only half the solution though: How is a user supposed to know which logo to look for to support DisplayPort?
All USB-C cables, even those without logos, identify themselves to the computer precisely (using USB PD), and my team reads that info now, and we eliminate a silent failure when the user uses a USB 2.0-only cable with a DP Dock or Monitor.
Many of our latest Chromebooks support USB4. USB4 is an advanced mode where the speed and limitations of the cable also matters, and we've built notifications to help the user when connecting to USB4 devices with a cable that can't support the new mode.
Our USB4 Chromebooks also support Thunderbolt 3 peripherals, and just like USB4, the speed and capability of the cable matters. Once again, we've built a notification to warn the user when a combination of cable and device don't mix.
We also detect conditions where the device is functional, but limited in speed because of the choice of cable (ie, cable's only 20 Gbps rated while the device is rated for 40 Gbps).
All of the above are notifications that occur to inform the user when something goes wrong, but what if you just want more info on the devices or cables you have plugged in? We built a diagnostic utility into M99+.
chrome://system/#typec_connector_class will display information about any USB Type-C partner and cable you attach. The output is only lightly processed from the raw objects we get from the devices themselves, but the info is there!