Computer cables carry data, video, audio, and power between your computer and other devices, such as monitors, docks, drives, and chargers. Adapters convert one type of connection into another, so you can plug a device into a port it was not originally designed for, such as connecting an HDMI monitor to a laptop that only has USB-C ports.
The right cable matters more than it might seem. Two cables with the same connector can support very different speeds, resolutions, and charging power. Using the wrong one can mean a monitor that will not reach its full resolution, slow file transfers, or a laptop that charges slowly.
This guide explains the most common connections, USB-C, HDMI, and DisplayPort, along with the adapters you are most likely to need and how to choose the right cable for each job.
What is USB-C?
USB-C is a small, oval, reversible connector used on modern laptops, tablets, phones, docks, and accessories. It can carry data, video, audio, and power through a single cable. USB-C describes the shape of the connector, not its speed. The capabilities of a USB-C port or cable depend on the standard it supports.
USB connector types
Connector | What it looks like | Common uses |
|---|---|---|
USB-C | Small, oval, and reversible | Modern laptops, phones, docks, chargers, displays |
USB-A | Rectangular; inserts one way | Keyboards, mice, flash drives, older PCs and chargers |
Micro-USB | Small and tapered | Older phones and small accessories |
USB speeds and names
USB standards have had several confusing names over the years. The USB Implementers Forum (USB-IF) now labels products by speed, such as "USB 10Gbps" or "USB 40Gbps," instead of technical names like "USB 3.2 Gen 2" or "USB4 v2" (Notebookcheck).
Current name | Maximum data speed | Older or technical names |
|---|---|---|
USB 2.0 | 480 Mbps | Hi-Speed USB |
USB 5Gbps | 5 Gbps | USB 3.0, USB 3.1 Gen 1, USB 3.2 Gen 1 |
USB 10Gbps | 10 Gbps | USB 3.1 Gen 2, USB 3.2 Gen 2 |
USB 20Gbps | 20 Gbps | USB 3.2 Gen 2x2 |
USB 40Gbps | 40 Gbps | USB4 (version 1) |
USB 80Gbps | 80 Gbps | USB4 version 2 |
Sources: Notebookcheck, Plugable.
What else USB-C can carry
Video: Through DisplayPort Alt Mode, USB4, or Thunderbolt, a USB-C port can drive an external monitor.
Power: Through USB Power Delivery, USB-C can charge laptops and other devices. See our chargers and power guide.
Thunderbolt: Thunderbolt 3, 4, and 5 use the USB-C connector with higher guaranteed capabilities. See our docking stations guide.
Not every USB-C port supports every feature. Check your device's specifications, and look for icons such as a lightning bolt for Thunderbolt or a display symbol for video.
USB-C and Thunderbolt cables: speed and power ratings
USB-C cables look alike, but they are not all the same. Each cable has two separate ratings: how fast it can move data and how much power it can carry. A cable that charges a laptop well may still transfer files slowly, and a fast data cable may not support high-wattage charging.
Power ratings
Cable rating | Maximum power | Typical use |
|---|---|---|
60W | 60 watts | Phones, tablets, and many thin-and-light laptops |
100W | 100 watts | Most laptops |
240W | 240 watts | High-power laptops, using USB Power Delivery 3.1 Extended Power Range (EPR) |
Certified cables can display both speed and power on their labels, such as "USB 40Gbps, 240W" (PCWorld).
Data speed and cable length
Faster passive cables are generally shorter, because high-speed signals weaken over distance. As a general guide, passive USB 10Gbps and 20Gbps cables are often up to about 1 meter, while passive USB 40Gbps cables are commonly limited to about 0.8 meters (Plugable). Longer high-speed cables usually use active electronics to keep the signal strong.
Thunderbolt cables
Thunderbolt cables use the USB-C connector but are certified for Thunderbolt's higher, guaranteed performance. A certified Thunderbolt 4 or Thunderbolt 5 cable also works as a full-featured USB-C cable, which makes it a flexible choice for docks and fast storage.
Tips for buying USB-C cables
Match the cable to the job: charging, fast data, video, or all three.
Read the label for speed (for example, USB 10Gbps or USB 40Gbps) and power (60W, 100W, or 240W).
Use the cable that came with your dock, monitor, or drive when possible, since it is matched to that device.
Choose certified cables from reputable brands for safety and reliable performance.
What is HDMI?
HDMI (High-Definition Multimedia Interface) is a digital connection that carries video and audio through one cable. It is the most common way to connect computers to TVs, projectors, and many monitors, and it is found on laptops, desktops, docks, game consoles, and streaming devices.
HDMI versions
Version | Maximum bandwidth | Typical capabilities | Cable to use |
|---|---|---|---|
HDMI 1.4 | About 10 Gbps | 1080p, and 4K at 30 Hz | High Speed HDMI |
HDMI 2.0 | 18 Gbps | 4K at 60 Hz | Premium High Speed HDMI |
HDMI 2.1 | 48 Gbps | 4K at 120 Hz and above, 8K at 60 Hz, variable refresh rate | Ultra High Speed HDMI |
HDMI 2.2 | Up to 96 Gbps | Higher resolutions and refresh rates, such as 4K at 480 Hz | Ultra96 HDMI |
The HDMI Forum released the HDMI 2.2 specification in 2025. It doubles maximum bandwidth to 96 Gbps and requires a new Ultra96 cable to reach its full potential (HDMI.org). HDMI 2.2 products are expected to begin appearing on TVs and monitors in late 2026 or early 2027 (TechRadar).
Tips for HDMI
Match the cable to your display's needs. For 4K at 120 Hz or higher, use an Ultra High Speed HDMI cable.
Look for the certification label on the packaging to confirm the cable has been tested.
Check port versions. A cable cannot add features that the laptop or monitor port does not support.
Know that HDMI labels can be broad. Devices labeled with a newer HDMI version do not always support every feature of that version, so check the specific features you need, such as refresh rate or variable refresh rate.
What is DisplayPort?
DisplayPort is a digital connection designed mainly for computer monitors. It carries video and audio and is common on desktop graphics cards, business monitors, and docking stations. DisplayPort signals can also travel over USB-C through DisplayPort Alt Mode, which is how many laptops drive external monitors.
DisplayPort versions
Version | Maximum bandwidth | Typical capabilities |
|---|---|---|
DisplayPort 1.2 | About 21.6 Gbps | 4K at 60 Hz; multiple monitors through daisy-chaining |
DisplayPort 1.4 | About 32.4 Gbps | 4K at 120 Hz and higher, 8K with Display Stream Compression (DSC), HDR |
DisplayPort 2.1 | Up to 80 Gbps | Very high resolutions and refresh rates for 4K, 8K, and beyond |
DisplayPort comes in full-size and Mini DisplayPort connectors. For DisplayPort 2.1 speeds, look for VESA-certified cables, which are labeled by bandwidth, such as DP40 or DP80.
Multi-monitor daisy-chaining
DisplayPort supports Multi-Stream Transport (MST), which lets you connect one monitor to another in a chain from a single port, as long as the monitors support it. This is useful for clean multi-monitor desk setups. See our docking stations guide.
HDMI vs. DisplayPort: which should you use?
HDMI | DisplayPort | |
|---|---|---|
Most common on | TVs, projectors, consoles, laptops, monitors | Computer monitors, desktop GPUs, docks |
Best for | Connecting to TVs and projectors; living-room setups | High-refresh-rate PC monitors and multi-monitor setups |
Multi-monitor daisy-chaining | Not supported | Supported with MST |
Audio return to a sound system | Supported with ARC or eARC | Not a typical use |
Over USB-C | Through adapters | Native through DisplayPort Alt Mode |
For PC monitors, DisplayPort is often the better choice, especially for high refresh rates. For TVs and projectors, HDMI is usually the only option. Our display features guide explains refresh rate and resolution.
Common computer adapters
Adapters let you connect devices that use different ports. They are especially useful for thin laptops with only USB-C ports.
Adapter | What it does | Common use |
|---|---|---|
USB-C to HDMI | Connects a USB-C laptop to an HDMI monitor, TV, or projector | Presentations and home TVs |
USB-C to DisplayPort | Connects a USB-C laptop to a DisplayPort monitor | High-refresh-rate monitors |
USB-C to USB-A | Lets USB-A devices, such as flash drives and mice, plug into USB-C ports | Older accessories |
USB-A to USB-C | Lets USB-C devices plug into USB-A ports | Charging or connecting newer devices to older PCs |
USB-C to Ethernet | Adds a wired network jack | Faster, more stable connections |
USB-C to 3.5 mm audio | Adds a headphone jack | Wired headphones and headsets |
DisplayPort to HDMI | Connects a DisplayPort output to an HDMI display | Desktop GPUs to TVs |
USB-C multiport adapter (hub) | Combines several ports in one adapter | Travel and hot-desking |
Active vs. passive adapters
Passive adapters simply reroute signals when both sides already speak the same language, such as USB-C with DisplayPort Alt Mode to DisplayPort.
Active adapters contain a chip that converts one signal type into another, such as DisplayPort to HDMI 2.1 at high refresh rates. Active adapters are often needed for higher resolutions and refresh rates.
Adapter tips
Check what your laptop's port supports. A USB-C to HDMI adapter only works if the USB-C port supports video output.
Match the adapter to your display's resolution and refresh rate. Some adapters top out at 4K at 30 Hz, which can feel sluggish.
Mind the direction. Some adapters work only one way, such as DisplayPort out to HDMI in.
Consider a dock if you need several adapters at once. See our docking stations guide.
How to choose the right cable or adapter
Identify both ends. Check the ports on your computer and on the device you want to connect, such as USB-C, USB-A, HDMI, or DisplayPort.
Decide what the cable must carry. Charging, fast data, video, or all three.
Match the speed or version. For example, choose USB 10Gbps or faster for portable SSDs, Ultra High Speed HDMI for 4K at 120 Hz, or DisplayPort 1.4 or 2.1 for high-refresh-rate monitors.
Match the power rating. For laptop charging, choose a USB-C cable rated for at least your charger's wattage, such as 100W or 240W.
Choose the right length. Shorter passive cables are more reliable at high speeds. Use active cables for longer runs.
Buy certified cables. Look for USB-IF, Thunderbolt, HDMI, or VESA certification labels.
Quick cable guide
You want to | Use |
|---|---|
Charge a laptop over USB-C | USB-C cable rated 100W or 240W |
Connect a fast external SSD | USB-C cable rated USB 10Gbps or faster, or a Thunderbolt cable |
Connect a 4K monitor at 60 Hz | HDMI 2.0, DisplayPort 1.2 or later, or a USB-C cable with video support |
Connect a high-refresh-rate monitor | DisplayPort 1.4 or 2.1, or Ultra High Speed HDMI |
Connect to a TV or projector | HDMI cable, or a USB-C to HDMI adapter |
Connect a Thunderbolt dock | The Thunderbolt cable that came with the dock, or a certified Thunderbolt cable |
Cables and adapters frequently asked questions
Are all USB-C cables the same?
No. USB-C cables share the same connector but can differ in data speed, charging power, and video support. Some support only USB 2.0 data speeds and basic charging, while others support 40 Gbps or 80 Gbps data and up to 240W. Check the cable's label or specifications.
What is the difference between USB-C and Thunderbolt?
USB-C is the connector shape. Thunderbolt is a high-performance standard that uses the USB-C connector and guarantees features such as high bandwidth, multiple-display support, and laptop charging. Every Thunderbolt 3, 4, or 5 port uses USB-C, but not every USB-C port supports Thunderbolt.
Can I connect a monitor to my laptop's USB-C port?
Yes, if the port supports video output through DisplayPort Alt Mode, USB4, or Thunderbolt. Look for a display icon or Thunderbolt symbol next to the port, or check your laptop's specifications. Then use a USB-C monitor cable or an adapter to HDMI or DisplayPort.
Is HDMI or DisplayPort better for gaming?
For PC monitors, DisplayPort often supports higher refresh rates and is widely used for gaming. HDMI 2.1 also supports high refresh rates and variable refresh rate, and it is the standard for TVs. Use whichever connection your monitor and graphics card support at the refresh rate you want.
Why won't my monitor reach its full refresh rate?
Common causes include a cable or adapter that does not support the needed bandwidth, an older port version on the laptop or monitor, or a display setting in Windows. Use a cable rated for your resolution and refresh rate, and set the refresh rate under Settings > System > Display > Advanced display.
Do expensive HDMI cables make a difference?
A certified cable that meets the needed standard works as well as a more expensive one of the same rating. Price does not improve picture quality, but certification and the correct rating, such as Ultra High Speed for HDMI 2.1, do matter.
Can I use a USB-C phone cable to charge my laptop?
Only if it is rated for enough power. Many phone cables are rated for 60W, which may charge some laptops slowly. Use a cable rated for at least your laptop charger's wattage.
What does an active cable or adapter do?
An active cable or adapter contains electronics that boost or convert the signal. Active cables support longer lengths at high speeds, and active adapters convert between different signal types, such as DisplayPort to HDMI at high refresh rates.
Related accessories glossary guides
Accessories glossary: What computer accessories are, plus key terms
Docking stations: Thunderbolt and USB-C docks for one-cable setups
Chargers and power: USB Power Delivery and charger wattage
External storage: Choosing the right cable for fast drives
Webcams: USB connections for external cameras
Display features: Refresh rate, resolution, and HDR
