Your laptop may be powerful, but limited ports can hold your workstation back.

The UGREEN CM639 8-in-1 USB-C Docking Station is designed for users who need more screens, faster data connections and reliable laptop charging from a single USB-C connection.

With two HDMI outputs and one DisplayPort, the CM639 can drive up to three external displays on compatible Windows systems. Each video output supports up to 4K@60Hz individually, giving you the flexibility to build a high-resolution multi-monitor workspace.

For demanding data workloads, the CM639 provides four 10Gbps USB data ports, including two USB-A 3.2 Gen 2 and two USB-C 3.2 Gen 2 ports. Connect fast external SSDs, storage devices, keyboards, mice and other high-speed peripherals without relying on a collection of separate adapters.

The dedicated USB-C Power Delivery input accepts up to 100W, with up to 85W passed through to the connected laptop while the remaining power is used by the docking station.

That combination makes the CM639 particularly suited to professionals who work across multiple applications, content creators working with large files, developers who need multiple screens, traders and analysts who monitor multiple windows, and anyone who wants a cleaner laptop-based workstation.

Key Features

1. Triple 4K Display Expansion

The CM639's biggest advantage is its multi-display capability.

It provides:

• 2× HDMI
• 1× DisplayPort
• Up to 4K@60Hz per output individually

Use multiple monitors to keep your email, browser, documents, spreadsheets, development tools or creative applications visible at the same time.

On compatible Windows systems, the dock can support extended multi-monitor configurations using MST. Actual resolution and refresh rate depend on the laptop's graphics capabilities, USB-C/DisplayPort implementation and available bandwidth.

2. Four 10Gbps USB Data Ports

Unlike basic USB-C hubs that rely on slower USB 3.0 connections, the CM639 provides 10Gbps USB 3.2 Gen 2 connectivity across its four data ports.

USB-A

2× USB-A 3.2 Gen 2

Ideal for:

• External drives
• Flash drives
• Keyboard and mouse
• Printers
• USB accessories

USB-C

2× USB-C 3.2 Gen 2

Ideal for:

• External SSDs
• High-speed storage
• USB-C peripherals
• Modern accessories

The USB-C data ports are data-only and do not provide video output or laptop charging.

3. 100W USB-C Power Delivery

Keep your laptop powered while your workstation is connected.

The CM639 accepts up to 100W USB-C PD input and can pass through up to 85W to the laptop, with approximately 15W reserved for operation of the hub itself.

This means one compatible USB-C charger can power both your laptop and the docking station.

Important: The actual charging power depends on your laptop, USB-C charger and cable.

4. 4K@60Hz HDMI and DisplayPort

For smooth, high-resolution desktop output, the CM639 supports:

• HDMI 1: up to 4K@60Hz
• HDMI 2: up to 4K@60Hz
• DisplayPort: up to 4K@60Hz

This is ideal for:

• Office monitors
• Professional displays
• 4K TVs
• Digital workstations
• Presentations
• Creative applications

For best results, use quality HDMI/DisplayPort cables and a host laptop capable of supporting the required display bandwidth.

5. Designed for Power Users

The CM639 is not just for adding a few missing ports.

It is designed for people who want to transform a laptop into a serious desktop-style workstation.

Ideal for:

Developers
Run your code editor, browser, terminal and documentation across multiple displays.

Content Creators
Keep your editing timeline, preview window and other applications visible simultaneously.

Finance & Business Professionals
Monitor spreadsheets, dashboards, email and communication tools across multiple screens.

Remote Workers
Create a professional multi-monitor home-office setup around your laptop.

IT Professionals
Connect multiple displays, high-speed storage and USB peripherals from one dock.

Ideal Workstation Setup

A typical setup could include:

Laptop → CM639 →

Monitor 1 via HDMI
Monitor 2 via HDMI
Monitor 3 via DisplayPort
External SSD via USB-C
Keyboard via USB-A
Mouse via USB-A
Laptop charger via USB-C PD

All connected through one USB-C docking station.

Important Compatibility Notes

USB-C Port Requirements

The laptop's USB-C port must support the required DisplayPort Alt Mode functionality for HDMI and DisplayPort video output.

A USB-C port that supports charging or data only may not support external display output.

Triple-Display Support

The CM639 is particularly powerful for Windows users with compatible hardware.

For Windows MST configurations, triple-display operation can be supported, but the available bandwidth of the laptop can affect the maximum resolution and refresh rate when multiple displays are connected simultaneously. Some configurations may limit all three displays to 4K@30Hz.

macOS

Multi-monitor functionality on macOS is more restricted than Windows and depends on the Mac model and its native external-display capabilities. The CM639 documentation notes display limitations on macOS, including mirroring behavior for multiple monitors on supported configurations.

Always check your laptop's USB-C and graphics specifications before purchasing if your primary goal is triple-monitor extended mode.

Why Buy the UGREEN CM639?

Three Displays From One Connection

Build a powerful multi-monitor workstation without connecting multiple individual adapters.

10Gbps Data Connectivity

Four high-speed USB 3.2 Gen 2 data ports provide significantly more bandwidth than basic USB 3.0 hubs.

Serious Workstation Expansion

The CM639 combines display expansion, high-speed USB connectivity and laptop charging into one compact docking station.

Perfect for Modern USB-C Laptops

If your laptop has powerful hardware but lacks ports, the CM639 gives you the connectivity needed for a more complete desktop-style setup.