Summary
The switch to USB Type-C and USB4 was supposed to flip the script. USB ports, cables, and communication protocols were a mess, with inconsistent specs and convoluted naming schemes. As it turns out, the USB Type-C hardware interface and USB4 communication protocol both fell into the same trap. USB4 could indicate a port or cable with a handful of specs and features, few of them guaranteed across all certified devices and accessories. And while many users think every cable or port using Type-C hardware meets USB4 standards, that isn’t the case.
In fact, USB4 should be the last thing you look for when evaluating a device, accessory, or cable’s capabilities. There are specific symbols and specs that will tell you how a USB-C port or cable will perform better than a USB4 logo. This is why the USB4 name isn’t as important as you think, and these are the logos you should look for instead.
Not all USB-C ports and cables are USB4
The connector doesn’t tell you the communication protocol
We’re familiar with USB Type-A, USB Type-B, and USB Type-C ports and connectors. For reference, “Mini USB” and “Micro USB” cables are variations of USB Type-B cables, and the full-size versions are used for things like printers and MIDI audio gear. You probably still use a mix of USB Type-A and USB Type-C devices and accessories for charging or data transfer. USB Type-A, USB Type-B, and USB Type-C are all hardware interfaces, otherwise known as ports or connectors. They represent the physical technology bridging the gap between two devices, accessories, or power sources.
Specifically, USB Type-C is a 24-pin reversible connector. A communication protocol like USB4 is used to share information between two devices using a hardware interface like USB Type-C. However, the USB Type-C connector can be used with various communication protocols. This means not every USB Type-C port or connector is using the USB4 standard. Additionally, there are multiple versions of USB4 that use the Type-C hardware interface. Simply seeing the USB4 logo or the Type-C connector doesn’t tell you the bandwidth, charging speed, or features supported by a cable or device.
USB4 cables commonly support 40Gbps speeds, but the minimum requirement is half that. There are 20Gbps USB4 cables that offer zero speed benefit compared to USB 3.2 Gen 2x2. At the high end, there are also USB4 V2 cables supporting up to 80Gbps bidirectional data transfer speeds. You could pick up a USB4 cable off the shelf without knowing whether it supports 20Gbps, 40Gbps, or 80Gbps speeds. The same goes for charging speeds, display resolutions and refresh rates, and DisplayPort versions. The same variety extends to ports, accessories, and anything else using the USB4 communication protocol.
When the USB4 brand can identify ports and connectors with wildly different capabilities, it becomes meaningless. USB4 doesn’t mean what you think it means, and that’s because, by itself, the USB4 logo doesn’t tell you the exact specifications of a port or connector.
Thunderbolt and USB4 both use USB Type-C
Not every USB4 port and cable can match Thunderbolt
You need more than the USB4 logo to understand the specs and features of a Type-C port or connector. Luckily, the USB Implementers Forum finally realized version numbers aren’t great at relaying the capabilities of a USB accessory to consumers. USB accessories should use new logos that display the data transfer rate (expressed in Gbps) and charging speed (expressed in W) directly on the cable and its packaging. Instead of looking for the USB4 brand, seek out logos like “40Gbps, 240W” or “20Gbps, 100W,” such as the ones in the chart below.
These logos and specs are actually insightful. While a USB4 port or connector can have a data transfer rate of up to 80Gbps and a charging speed of up to 240W, you won’t be able to tell them apart without these icons. Compliant USB-C cables are starting to list their data and charging speeds prominently, making it easier to identify which is a USB4 20Gbps cable and which is a USB4 V2 80Gbps cable. However, older and non-compliant USB-C cables can omit this information entirely. It’s also rare to see these icons directly on hardware, and a USB4 V2 80Gbps cable won’t do you any good if your phone or laptop is limited to a slower USB version.
USB4’s minimum requirements are lower than consumers expect, which is why premium devices, cables, and accessories opt for Thunderbolt. Thunderbolt is a communication protocol — one different from USB — that also uses the USB Type-C connector. The Thunderbolt icon helps you spot a compatible cable, device, or accessory. A Thunderbolt 4 or Thunderbolt 5 cable is backwards-compatible with USB4, but it has much higher minimum requirements.
For example, Thunderbolt 5 requires bidirectional data transfer speeds of 80Gbps. With a “Bandwidth Boost” mode, it can shift that bandwidth to provide 120Gbps unidirectional speeds, leaving 40Gbps for the other direction. It also mandates 140W charging speeds, whereas the USB4 requirement is just 7.5W. Thunderbolt 5 supports DisplayPort 2.1 and can drive up to three 8K displays at 60Hz refresh rates. In other words, Thunderbolt 5 ports and cables truly support the specs and features buyers want from USB4 accessories. Only the best USB4 V2 cables support these features, while Thunderbolt 5 bakes them into every single certified device, cable, or accessory.
The USB4 logo doesn’t tell you everything
Check a cable or port’s data and charging speeds before buying
USB4 has only been on the market for roughly half a decade, and there are already too many variants to keep track of. A basic USB4 cable could support 20Gbps or 40Gbps speeds, and a newer USB4 V2 cable might bump that up to 80Gbps. The problem is, the USB4 logo only guarantees the bare minimum. That equates to 20Gbps data transfer speeds and a mere 7.5W of USB Power Delivery, which isn’t even enough to beat older USB standards, such as USB 3.2 Gen 2x2. The USB4 logo alone isn’t informative.
Instead, you should seek out the data transfer speed and power delivery speed listed for a specific device, cable, or accessory before buying it. Data speeds are expressed in Gigabits per second (Gbps), whereas charging speeds are expressed in watts (W). For both, higher values are better. If you want the best USB Type-C speeds available, you’re looking for 80Gbps data speeds and 240W charging speeds. Those with devices that support Thunderbolt 5 can find compatible cables and guarantee they’re getting fast charging and data transfer rates.
For everyone else, a keen eye is required to navigate the messy USB Type-C and USB4 landscape. Looking for the Type-C connector or the USB4 logo isn’t enough to ensure you’re picking up the right cable.
Satechi USB4 V2 Pro Cable
- Brand
- Satechi
- Cable Type
- Works with Thunderbolt 4, Thunderbolt 3, USB4, USB 3.2/3.1/3.0/2.0
- Length
- 3.9 ft / 1.2m
- Data Transfer Rate
- 80Gbps bidirectional
- Charging Rate
- 240W
- USB Version
- USB4 Version 2.0 The Satechi USB4 V2 Pro cable is a high-end USB cable supporting 80Gbps bidirectional data transfer and up to 240W charging speeds. The cable also supports an external display at up to 8K at 120Hz or 4K at 240Hz. It’s backwards compatible with Thunderbolt 4, Thunderbolt 3, USB4, and USB 3.2/3.1/3.0/2.0.