Universal Serial Bus (USB) has become the standard interface for connecting devices and transferring data. As our digital world has evolved to deal with ever larger file sizes and power-hungry devices, USB has needed to advance as well. USB 3.0 and USB 3.1 represent the latest versions aimed at delivering faster speeds and better power delivery to keep pace with modern technology demands.
But with confusingly similar names and overlapping capabilities, it can be difficult to understand exactly what the differences are and when one version is preferable over the other. This guide breaks it down in practical terms – read on to learn how to choose the right USB standard for your needs.
A Brief History of USB Standards
Since its introduction in the late 1990s, USB has gone through several major revisions. Each version brought new enhancements:
- USB 1.0/1.1 – Initial release supporting data rates up to 12 Mbps. Primarily targeted low-bandwidth devices.
- USB 2.0 – Major upgrade launched in 2000 delivering speeds up to 480 Mbps. Became widespread and replaced earlier USB.
- USB 3.0 – First major speed boost since USB 2.0. Released in 2008 with 5 Gbps transfer rates.
- USB 3.1 Gen 1 – Minor revision of USB 3.0 spec. Same 5Gbps speed but more power efficient.
- USB 3.1 Gen 2 – Next major update doubling 3.0 speed to 10 Gbps. Released in 2013.
As you can see, the naming convention has been inconsistent. USB 3.0 and USB 3.1 Gen 1 refer to essentially the same 5 Gbps standard. Only USB 3.1 Gen 2 delivers the newer, faster 10 Gbps transfer rates.
With speed and power needs accelerating, USB 3.1 Gen 2 offers advantages over USB 3.0 for many modern use cases. However, USB 3.0 maintains benefits around cost, compatibility and accessibility.
USB 3.0 vs. 3.1 Gen 2 – Key Differences
Here are some of the core distinctions between the USB 3.0 and USB 3.1 Gen 2 standards:
1. Speed
This is the primary difference – USB 3.1 Gen 2 simply has newer architecture providing double the data transfer rates of USB 3.0:
- USB 3.0 – Up to 5 Gbps (640 MB/sec)
- USB 3.1 Gen 2 – Up to 10 Gbps (1,280 MB/sec)
While USB 3.0 is fast enough for common tasks like transferring photos, music or video from a camera or flash drive, the extra speed of USB 3.1 Gen 2 unlocks more advanced real-time applications.
2. Power Delivery
USB 3.1 Gen 2 supports significantly higher power output over its cable, removing a bottleneck some high-powered devices faced with USB 3.0.
- USB 3.0 – 900 mA (4.5W)
- USB 3.1 Gen 2 – Up to 100W
This expanded power capacity suits power-hungry electronics like higher-end tablets, laptops and gaming gear that need robust charging and data delivery over a single port/cable.
3. Efficiency
Thanks to a more efficient data encoding scheme (128b/132b), USB 3.1 Gen 2 delivers its speed boost while also consuming less power relative to achieved bandwidth. Less encoding/decoding overhead means power savings.
4. Connector & Cable
USB 3.1 Gen 2 fully incorporates the newer USB-C connector standard in addition to more traditional USB-A and USB-B connections:
- Reversible/symmetrical shape plugs in either orientation
- Enables slim, high-performance device designs
- Facilitates alternate modes like display, power and data delivery
However, to achieve its fast 10Gbps USB 3.1 Gen 2 transfers, maximum cable length is shorter vs. USB 3.0:
- USB 3.0 – 3 meter cables
- USB 3.1 Gen 2 – 1 meter cables
Longer cables can degrade signal integrity at these fast speeds.
Backward Compatibility
Importantly, both USB 3.0 and USB 3.1 Gen 2 maintain backward compatibility with earlier USB standards. So you can still use older USB devices or cables, just limited to those lower maximum speeds.
Conversely, plugging a USB 3.1 Gen 2 device into older USB ports limits the device to those older specs. The port/cable is always the speed bottleneck.
Key Benefits of USB 3.1 Gen 2
Based on the differences highlighted above, what are the major advantages USB 3.1 Gen 2 provides over the older but still very common USB 3.0 standard?
1. Faster File Transfers
The raw speed doubling to 10 Gbps data transfer rates is the headline enhancement. For large files like uncompressed video, creative assets, backups and virtual machine disks, etc. the difference between 5 Gbps and 10 Gbps is significant. Backup tasks run faster. Video transfers at full resolution rather than needing compression.
2. High Resolution Video Output
A great secondary benefit of USB 3.1 Gen 2 is its ability to output very high resolution video signals to displays or TVs. Content up to 8K resolution can be delivered over a USB 3.1 Gen 2 cable/port combo thanks to DisplayPort and HDMI alternate modes.
3. Charging High Power Devices
With up to 100 watts delivery possible, USB 3.1 Gen 2 can both charge and provide connectivity to power-hungry gear including higher-end laptops, tablets and gaming devices that previously may have required standalone AC adapters. Reduces cable clutter!
4. Future-Proofing Connectivity
While USB 3.0 remains very common, computing/devices continue advancing. As more powerful peripherals and storage devices launch moving forward, USB 3.1 Gen 2‘s boosted capabilities helps keep some future-proofing flexibility.
When to Stick with USB 3.0
For all its benefits, USB 3.1 Gen 2 still comes at a price premium over the very mature USB 3.0 standard – in terms of cables and the device/host interfaces. And for many everyday uses, 3.0 has sufficient performance. So there remain good reasons to stick with USB 3.0 as well:
1. Budget/Cost Factors
USB 3.0 ports, cables, hubs and devices are ubiquitous and economical. If project budgets are a concern, utilizing USB 3.0 hardware can save noticeable money without significant compromise in functionality. As long as its approx. 5Gbps speed isn‘t the bottleneck, USB 3.0 makes sense for many cost-conscious deployments.
2. Hardware Availability/Compatibility
With USB 3.0 released back in 2008, it has had well over a decade to reach mass market adoption. You‘re much more likely to already have USB 3.0 capability in laptops, desktops and mobile devices you own and interface with. Where maximum compatibility or accessibility with existing hardware is needed, USB 3.0 provides that flexibility.
3. Everyday/Moderate Speed Needs
Do you need to transfer giant 100GB video projects in minutes? For more ordinary workloads like documents, photos, music and smaller file transfers, USB 3.0‘sapprox. 400-500MB/sec speeds are still ample. Faster is great but if "fast enough" works, sticking with USB 3.0 makes sense for cost and convenience factors in many everyday scenarios.
Tips for Choosing Which USB Standard To Utilize
Based on the information above, what‘s the best way to decide whether to seek out USB 3.1 Gen 2 vs remaining with USB 3.0 solutions in a particular situation?
Here are a few tips:
- If budget is tight, start by checking if USB 3.0 meets your core transfer/connectivity requirements before paying extra for USB 3.1 Gen 2 performance.
- Conversely, if fastest speeds possible are critical – for transferring uncompressed 8K video for example – only USB 3.1 Gen 2 hits that 10Gbps benchmark so far.
- For power users that also value future-proofing, USB 3.1 Gen 2 capable interfaces offer nice headroom even if not fully tapped today.
- Check peak power requirements for devices you intend to connect/charge. If anything draws over 4.5W (typical USB 3.0 max), USB 3.1 Gen 2‘s potentially 100W should accommodate.
Evaluate these factors relative to your specific use situations, and the choice between the two capable USB standards becomes an easier equation!
I hope this breakdown has helped explain what sets USB 3.1 Gen 2 and USB 3.0 apart, as well as when leveraging the strengths of each can be beneficial. Thanks for reading! Let me know if you have any other USB-related topics I can help shed some light on.
