USB4 vs. USB-C: What's the Difference?

Patrick_Yu

Most modern devices won't work without USB cords and chargers, from charging your mobile to connecting your mouse. You have a tangle of USB cords that only work with some devices, but USB-4 and USB-C change that with a universal port.

USB4 is the latest generation of connectors. The promise is you can move large files between devices much quicker than before - a 4k video in under 20 seconds. You can transfer data up to 40Gbps. USB4 is faster and supports simultaneous data transfer, video, and charging. Plus, it's backward compatible with older USB standards.

So what exactly is USB4, and how is it different from USB Type-C? What will it mean for you moving forward? This article will cover all you need to know about this latest USB standard.

What is USB? 

USB stands for Universal Serial Bus. USB is a standard connector connecting your external devices and peripherals to your computer. USB-connected devices enable your computer to communicate with a broad range of devices:

• external hard-drive 
• flash drive 
• mouse  
• keyboard 
• digital camera 
• printer 
• mobile phone 

USB is a plug-and-play connection and allows hot-swapping of devices. It's fast and convenient as you can connect your printer, and your operating system discovers it without needing to reboot your computer. 

Who sets the USB Standard? 

The USB Implementers Forum (USB-IF) develops and sets the USB standard. Their goal is to create a standard that works across multiple devices, unifying the myriad of technologies down to one universal standard. 

What is USB-C?  

USB Type-C connector or USB-C is a newer standard connector that can transmit data and power on a single cable. The C is one of the three common USB connector types:

• Type A
• Type B
• Type C

With Type A, we've all been frustrated with trying to plug a USB in one way, trying the other, and then realizing the first way was correct. USB-C's flattened oval shape solves this problem as the connectors are reversible and work whichever direction you plug it in. It's similar to Apple's Lightning plug.

USB-C is compatible with both PC and Mac. Plus, its ports and cables are compatible with Thunderbolt ports and cables. So, as devices become more and more cross-platform, everyone benefits from USB-C.

How fast is USB-C? 

USB-C is just the physical design of the ports and cables. So, the transfer speed can vary from 5 to 20Gbps.

Here's a breakdown of the four main USB protocols:

1) USB 3.2 Gen 1 

In 2009, the first USB-C was introduced with maximum transfer speeds of 5GBps.

2) USB 3.2 Gen 1x2 

The most popular USB-C protocol, released in 2014, has a 10Gbps maximum transfer speed.

3) USB 3.2 Gen 2x1  

These ports also have 10Gbps maximum speeds but support only USB Type-A.

4) USB 3.2 Gen 2x2  

Released for USB-C in 2017, this protocol has a 20Gbps maximum speed.

How to choose the correct USB-C? 

To confuse matters, they come with multiple marketing names. To verify if the USB-C port supports 10 or 20Gbps transfers, look at the packaging for:

• 10Gbps: USB 3.2 Gen 1x2 or 10Gbps or SuperSpeed USB 10Gb  
• 20Gbps: USB 3.2 Gen 2x2 or 20Gbps or SuperSpeed USB 20Gb

On the positive side, older devices do work with the newer specs. Although not at top speed, your old USB-C flash drive will still work with your new laptop.

How fast can USB-C connections charge? 

A notable difference between USB-C and previous versions is it can deliver enough power to charge your laptop or smartphone. Many of our Chromebooks use a USB-C connection adapter for charging.

USB-C is just the physical connector - so how fast it will charge is based on the USB version supported by the device you're using. Instead of being limited to around 5 watts of power for charging, USB-C PD can charge your device at 100 watts - up to 70% faster than standard 5W charging.

What can I use USB-C for? 

USB-C shines in how it transmits video signals from one device to another. The video and audio quality is far superior to an older USB connector.

USB-C can replace a conventional HDMI cable, provide higher video quality, and connect devices easier.

USB4 is the newer USB standard that follows on from USB 3.2.

What is USB4? 

USB4 is the latest connectivity standard and is available only via the USB-C connector. Released in 2019, USB4 is the fifth major version and promises:

• faster transfer speeds (up to 40Gbps)
• better video bandwidth management
• support for 4K and 8K displays
• supports data transfer, video, and charging all at the same time
• optional Thunderbolt 3 compatibility

Finally, USB4 is backward compatible with previous USB versions.

How fast is USB4? 

USB4 has two main speeds:

• USB4 20Gbps: up to 20Gbps transfer speeds
• USB4 40Gbps: up to 40Gbps

USB4's dual-line cables allow more data to travel, improving bandwidth and data transfer speed. USB4 can transfer data faster than most USB-C devices, which max out at 20Gbps. USB4 matches Thunderbolt 3's 40Gbps transfer speed.

The benefit is you can transfer large files like 4K videos in seconds.

Fast charging via USB Power Delivery (USB PD) 

Unlike USB-C, USB4's power capability is standardized and must comply with the USB Power Delivery (USB PD) specs. Now, every USB4 cord requests higher watts from chargers.

USB PD delivers up to 100 watts of power, allowing you to charge your laptop (inbound) and smaller devices like an iPhone (outbound). Plus, you can charge more devices from a single port. 

USB4 supports DisplayPort 2.0 

USB4 allows you to connect a display to your computer and uses DisplayPort Alt Mode 2.0 to provide high-quality video in 8K HDR.

USB4 is ideal for connecting multiple monitors and external video displays. Through DisplayPort and PCIe tunneling, USB4 can send video and data simultaneously by sharing resources. This bandwidth allocation is dynamic and shared as needed and uses protocol tunneling to handle things more efficiently. For example, if your external drive requires 20% of bandwidth, the remaining 80% is allocated for video transfer.

Backward compatible 

USB 4 supports older USB devices, as long as they fit into the port. If they don't, consider buying a converter. You'll just need to know if your older USB tech uses a USB-A or USB-C design.

Is it USB4 or USB 4? 

The official name is USB4, not USB 4. There isn't a space between the "USB" and the "4." The goal is to stay simple with just USB4 and avoid iterations such as 4.1.

Which USB type is best for you? 

After reading about the differences between USB-C and USB 4, you'll realize if you buy USB4, it uses the USB-C design by default.

So, it makes sense to go with USB4 as it's the next generation and boasts wide-ranging compatibility. It charges faster, transfers data in seconds, and uses fewer ports than older USB technologies.