I already own a USB-C dongle. Can I use it with Thunderbolt?
Yes, you can connect the dongle to a Thunderbolt port. But the 10Gbps dongle won't magically transform into a 40Gbps Thunderbolt port, as there's circuitry within the dock that allows it to work with your laptop's high-speed Thunderbolt port. However, there's nothing saying that you can't connect the dongle to an available USB-C port on the Thunderbolt dock itself, either. If your laptop has two Thunderbolt ports, you can also attach a Thunderbolt dock to one port, and the dongle to the other.
That solution will add more clutter to your desk, but it might allow you to buy a cheaper, budget dock, too. It's up to you!
My laptop says it has a USB4 port, not Thunderbolt. Can I use it with a Thunderbolt dock?
Probably. USB4 ports typically appear on laptops with AMD Ryzen processors inside. USB4 and Thunderbolt 4 are compatible and functionally equivalent. (Though Thunderbolt is an open standard, Intel declines to certify non-Intel hardware. That means that Ryzen laptops end up with USB4 ports, and Intel Core laptops include Thunderbolt.)
USB4 is essentially a subset of Thunderbolt 4, mainly designed as an I/O specification.
As a subset of Thunderbolt 4, a USB4 device will run just fine plugged into a Thunderbolt 4 port. But dock makers tell us that a Thunderbolt 4 device may not work as expected when plugged into what is specifically a USB4 port. Instead, most hubs and docks are marketed as Thunderbolt 4, while most devices (like an external SSD) are designed around USB4. (We test Thunderbolt docks on Thunderbolt laptops.) There are USB4 docks, however, which you'll find above in our list of best picks.
USB4 Version 2 is a standard that will propel USB4 to 80Gbps, just like Thunderbolt 5. I haven't seen any docking stations marketed as USB v2 (also known as USB80Gbps), however.
Note that Thunderbolt 3 and 4 require at least 15W to power devices plugged into the Thunderbolt port, such as a bus-powered hard drive. USB4 requires just half that.
I did try to connect a Thunderbolt 5 dock to a USB4 laptop, and it didn't work. It should! It may just be a driver issue.
What differentiates a DisplayLink USB-C docking station from a Thunderbolt dock?
A DisplayLink USB-C docking station is a new category of docking station. They're often marketed just as a USB-C docking station, unfortunately, though the DisplayLink logo features prominently on the box. The key here is that the DisplayLink technology (now owned by Synaptics) uses data compression between your PC and the dock to approximate a Thunderbolt experience (a pair of 4K displays at 60Hz, plus additional peripherals) across the narrower, slower USB-C bus. You'll need to install a software driver for your PC to communicate with the DisplayLink chip built into the dock.
The advantage here is twofold. First, DisplayLink allows you to "cheat" and get a Thunderbolt dock experience on an older laptop. Alternatively, even if you do own a laptop with a Thunderbolt port, you may be able to find a DisplayLink USB-C dock for a cheaper price than Thunderbolt. This is a viable solution, especially if you don't mind not playing PC games.
Our separate story on DisplayLink docks has more. For a while, DisplayLink offered a consistently cheaper option than Thunderbolt. Older Thunderbolt technologies and tariffs have now muddled those waters that the distinction isn't as clear-cut.