But it is complicated, the short answer is. Although the same physical connection is adopted, they are two different technologies that possess varied capabilities. Such a mix is expensive to users not only in time and money but also in frustration as the performance of a so-called universal cable falls short of expectations, Thunderbolt, and USB.
It is worth knowing the differences to all those who invest in contemporary gadgets, cables, or docking options. Regardless of whether you are configuring your workstation, have more questions in upgrading your laptop setup, or you are simply wondering why that fancy cable is not living up to your expectations, this guide will help you understand how data transfer works.
What Is USB-C?
USB-C is the connector standard – it is the physical shape of the port. It’s meant to be universal, to support multiple protocols and standards with a single reversible connector universal serial bus.
Again, the only thing you need to know is that USB-C doesn’t specify speed or functionality. A USB-C port is capable of carrying everything from simple USB 2.0 (480 Mbps) all the way up to USB4 Version 2.0 (up to 120 Gbps). This flexibility means USB-C is very versatile, but it’s also confusing to the consumer Thunderbolt docking stations.
USB-C ports are backwards compatible – so newer devices can be used with older cables and peripherals, but their performance is limited to the lowest common denominator. Connect multiple devices.
USB-C Versatility and Standards
What makes USB-C special is that it can carry different protocols at the same time. A single USB-C port can be used to transfer data, output video, and deliver power all at the same time video signals.
It needs support for dual 4K screens, and it needs wake-from-sleep. They all have different top speeds and abilities.
Power transfer rates by USB-C can vary from a simple 5V charge to up to 240W with USB Power Delivery 3.1, and it can therefore do everything from charge smartphones to connect to top-end laptops Thunderbolt connection.
What Is Thunderbolt?
Thunderbolt is the high-performance protocol developed by Intel, which in recent versions uses the USB-C connector (Thunderbolt 3, 4, and 5). The earlier Thunderbolt 1 and 2 used Mini DisplayPort connectors.
Consider Thunderbolt to be a premium highway system with USB-C as the physical onramp to Thunderbolt. Under the hood, the port is identical; however, Thunderbolt offers guaranteed performance levels, advanced video capabilities, and features you can only get with Thunderbolt, such as daisy-chaining multiple devices difference between thunderbolt.
Thunderbolt ports are engineered with more stringent requirements and often come with dedicated controller chips to maintain uniform high-speed performance across all devices connected to the port.
Thunderbolt Evolution: Versions 3, 4, and 5
| Version | Connector | Max Bandwidth | Display Support | Power Delivery | Notes |
| Thunderbolt 3 | USB-C | 40 Gbps | Dual 4K | Up to 100W | Transition from proprietary connectors to USB-C |
| Thunderbolt 4 | USB-C | 40 Gbps | Dual 4K | Up to 100W | Stricter compliance, better security, and wake-from-sleep mandatory |
| Thunderbolt 5 | USB-C | 80 Gbps (burst up to 120 Gbps for video) | 8K or dual 4K at higher refresh rates | Up to 100W | Advanced video & high-speed performance, backward compatible |
Thunderbolt 3 introduced the USB-C connector with 40 Gbps speeds, dual 4K display support, and 100W power delivery. This version marked the transition from proprietary connectors to the universal USB-C standard USB Implementers Forum.
Thunderbolt 4 maintained the same 40 Gbps speed but added stricter requirements for manufacturers, ensuring better compatibility and security features. It mandates support for dual 4K displays and wake-from-sleep functionality to transmit data.
Thunderbolt 5, the latest version, doubles bandwidth to 80 Gbps with burst speeds up to 120 Gbps for video applications. It can drive displays up to 8K resolution or dual 4K displays at higher refresh rates, external monitors.
Core Differences: Speed Comparison
| Feature | USB-C | Thunderbolt 3 & 4 | Thunderbolt 5 |
| Speed | 480 Mbps – 120 Gbps (varies) | 40 Gbps (consistent) | 80 Gbps (burst up to 120 Gbps for video) |
| Performance Guarantee | No | Yes | Yes |
| Real-world 100GB File Transfer | USB 2.0: ~33 min USB 3.2 Gen 2×2: ~4 min | ~20 sec | Faster due to higher bandwidth |
Wake-from-Sleep and Compatibility
| Feature | Thunderbolt 3 | Thunderbolt 4 | Thunderbolt 5 |
| Wake-from-sleep support | Optional | Mandatory | Mandatory |
| Security & Compatibility | Standard USB-C | Stricter compliance & better security | Advanced video & high-speed, backward compatible |
The biggest difference is guaranteed versus variable performance. USB-C ports can transfer speeds ranging from 480 Mbps to 120 Gbps, depending on the version of the USB standard being used.
Thunderbolt ensures stable, high-speed performance. Thunderbolt 3 and 4 support just 40 Gbps, while Thunderbolt 5 offers up to 80 Gbps bandwidth replay with video bandwidth boost capabilities of 120 Gbps.
For practical purposes, this means that moving a 100GB file will take around 33 minutes over USB 2.0, 4 minutes over USB 3.2 Gen 2×2, and only 20 seconds over Thunderbolt 3/4.
Power Delivery Capabilities
Both USB-C and Thunderbolt are compatible with USB PD standards, and current implementations can support up to 240W. However, the cable and the device specifications are more important than the connector type.
Thunderbolt cables are generally constructed to higher standards and more reliably support the full power delivery range compared with generic USB-C cables, which can be stuck at lower wattages.
Always look at your individual cable and device ratings instead of assuming the highest power delivery capacity based solely on connector type.
Video Output Performance
DisplayPort Alternate Mode power delivered over USB-C can power high-resolution displays, usually up to 8K at 60Hz or dual 4K displays, depending on the implementation.
Thunderbolt always provides increased video bandwidth. Thunderbolt 3/4 supports up to 5K displays or two 4K displays, and Thunderbolt 5 supports 8K displays at higher refresh rates or multiple 4K displays.
Consistency is the most important aspect here – while Thunderbolt promises video performance, the performance of USB-C video is all over the map, depending on the device and its implementation.
Compatibility Considerations
Thunderbolt ports are compatible with most USB-C cables and devices, although you will only benefit from USB speeds and functionality.
However, if you use USB-C cables with Thunderbolt devices, they might not work to reach maximum performance. For the best speeds, video quality, and access to features, be sure to connect Thunderbolt devices with certified Thunderbolt cables.
Some active Thunderbolt cables, especially optical ones that are meant for long distances, are not compatible with standard USB devices at all.
Can USB-C Cables Work with Thunderbolt Ports?
Yes, the majority of USB-C cables should be compatible with Thunderbolt ports, but the performance will be limited to the USB specification of the cable. So even if you connect your device to a USB 2.0 port and attach our Thunderbolt USB 2.0 cable to the port, in reality, the USB 2.0 port will only be able to give the device about 480 Mbps.
To ensure optimal performance, it’s best to use USB4-certified cables that are specifically optimized for Thunderbolt compatibility. These cables offer the flexibility to function in an optimal way with both USB and Thunderbolt devices.
Passive cables less than 2 meters tend to provide the best compatibility between both standards, with the longer or active cables often featuring specific restrictions.
Will Thunderbolt Cables Work with USB-C Devices?
Thunderbolt cables will usually work with USB-C devices, particularly passive cabling for short distances. For standard USB applications, these cables tend to perform very well.
However, there are some Thunderbolt-compatible cables that are designed for specific purposes and may not be compatible with standard USB devices, especially those that are intended for longer distances or require special professional connections.
To avoid wasting money, it’s best to verify USB compatibility in any case, either by checking the specifications of the cable or manufacturer documentation.
Identifying Thunderbolt-Enabled Devices
Thunderbolt-enabled devices identify their ports by looking for the telltale lightning bolt icon next to USB-C ports. This little symbol is the universal symbol for Thunderbolt compatibility.
Some manufacturers also label the ports with the words “Thunderbolt” or “TB3/TB4/TB5.” Device specs and manuals will also clearly identify Thunderbolt support.
To be safe, if you don’t see the lightning bolt symbol, you can assume the USB-C port only supports standard USB protocols, even if it does have high-speed data transfer or video output support.
Choosing the Right Cable
To ensure maximum versatility, opt for USB4-certified cables that specifically support Thunderbolt 3, 4, and 5 compatibility. These cables are designed specifically for use with USB and Thunderbolt devices.
Careful consideration should be given to passive versus active cable designs. Passive cable is the most compatible cable type, best for short distances (less than 2 metres), whereas active cables may offer longer connectivity or higher speed but at a cost in compatibility.
Always ensure you match power delivery specifications to your power needs, as high-wattage devices such as gaming laptops or professional workstations will need 100W+ power delivery.
Making the Smart Purchase Decision
Check your use case before buying premium cables. If you’re just using standard peripherals and you don’t need extreme speeds, basic USB-C cables may be fine.
Professional uses: If you are working in a professional setting where you use high-resolution displays or transfer large files between devices, consider investing in certified Thunderbolt cables for optimal performance and reliability.
Future-proofing your setup: You may not use the full capabilities of your devices, but by selecting cables that support the latest standards, you’re future-proofing your setup to accommodate future upgrades and expansions.
