A docking station promises one cable for everything. Whether it delivers depends on three numbers that are usually buried in a specification table: how much power it passes through, how many displays it can drive, and how fast its data ports actually run.
Get those wrong and the dock becomes another device to troubleshoot. This guide covers what to check, in the order that matters.
First: do you actually need a dock?
Before buying anything, check whether your monitor can do the job. Many monitors now offer USB-C with power delivery and a couple of downstream USB ports. Plug the laptop into the monitor and you get charging, video, and a place for a keyboard and mouse, with no extra box on the desk.
A dock earns its place when you need more than that: several displays, wired networking, audio, card readers, or the ability to swap between two computers.
If a monitor can cover your needs, spend the money on the monitor instead.
Power delivery: the number that causes the most problems
A dock passes power from its own adapter through to the laptop. If that pass-through is lower than what the laptop wants, the battery charges slowly, and under heavy load it may not charge at all.
What to do:
- Find your laptop's recommended charger wattage. It is usually printed on the charger or listed in the specification.
- Choose a dock whose pass-through meets or exceeds it. A dock that supplies less is not necessarily useless, but you should know you are trading charging speed.
- Check whether the dock's own adapter is included. Some docks ship without one and expect you to supply a charger, which changes the total cost.
Be sceptical of a single headline wattage figure. A dock may advertise a high total while reserving part of it for its own ports, leaving less for the laptop.
Displays: the limit that is easy to miss
Display support is where docks most often disappoint, because the limit depends on the laptop as much as on the dock.
Three things decide what you get:
- How many displays the dock can drive, which is stated.
- How many the laptop can drive, which is a property of the machine and its graphics.
- The resolution and refresh rate, because a dock that handles two displays at a modest resolution may not handle the same two at a high one.
If you run two external monitors, confirm both numbers: what the dock supports and what the laptop supports. A dock cannot add display outputs the laptop does not have.
Also check the physical outputs. A dock with two of the same connector is simpler than one that needs an adapter for the second screen, and adapters are a common source of a blank display.
Ports: count is less important than speed
Two docks with the same number of USB ports can behave very differently.
- Data speed varies a lot between ports on the same dock. A fast port and a slow port look identical. If you move large files, check which ports are which.
- Wired networking is worth having if the room's wireless is unreliable. A dock with Ethernet is often the simplest fix for a flaky connection.
- Card readers matter if you use a camera. Otherwise they are clutter.
- Audio jacks are increasingly unnecessary, since most headsets connect over USB or wireless.
For most desks, a sensible mix is: enough USB ports for a keyboard, a mouse, and one spare, plus Ethernet if the wireless is poor.
Heat, cables, and the small annoyances
A dock is a small computer. It gets warm, and some get warm enough to throttle.
- Placement matters. A dock under a monitor stand with no airflow runs hotter than one standing in the open.
- The host cable is the weak point. It is the cable you plug and unplug most, so a dock with a captive cable cannot have that cable replaced when it wears out.
- Firmware exists. Some docks need updates to fix display or charging behaviour, and the update process is rarely obvious. Check that the manufacturer provides updates at all.
A short checklist
- Check whether your monitor can already do charging, video, and a couple of USB ports. If so, skip the dock.
- Find your laptop's recommended charger wattage and match it with the dock's pass-through.
- Confirm the display limit of the dock and of the laptop, at the resolution and refresh rate you actually use.
- Prefer matching physical outputs so you do not need adapters.
- Check which USB ports are fast and which are slow.
- Add Ethernet if the room's wireless is unreliable.
- Give the dock airflow, and prefer a replaceable host cable.
- Confirm the dock ships with its own power adapter.
A dock is worth buying when it removes cables rather than adding a box. If a monitor can do the same job, the monitor is the better purchase.
Sources and further reading
- USB Implementers Forum (USB-IF). Publishes the USB Type-C and USB Power Delivery specifications, and the certified-logo programme. When a dock states a wattage or a data rate, this is the body that defines what those terms are allowed to mean.
- VESA, DisplayPort Alt Mode over USB Type-C. The standard that lets a USB-C port carry video, which is why the number of displays a dock supports depends on the laptop as much as on the dock.
- Your laptop manufacturer's power and display specifications. The recommended charger wattage and the maximum number of external displays are properties of the machine, and no dock can exceed them.