Thunderbolt 3 vs 4 for Demanding Setups

If you think Thunderbolt 4 is a faster version of Thunderbolt 3, think again! In this post, we’re going to simplify the differences in speed, display support, and other features for an informed decision.

What is Thunderbolt 3?

Thunderbolt 3 was released in 2015 and it was quite revolutionary at the time in the way it combined data transfer, video output, PCIe bandwidth, and charging capabilities in a single, compact USB-C connector. With speeds up to 40Gbps, four times faster than USB 3.1, Thunderbolt 3 allows for the rapid transfer of large files, such as 4K videos and high-resolution images.

Thunderbolt 3 also supports two 4K displays @ 60 Hz, making it ideal for professionals and creatives who require high-resolution visuals.1 Additionally, it provides up to 100W of power delivery for charging.

The adoption of the USB-C connector for Thunderbolt 3 also made it a lot more versatile and compatible with a wider range of devices.

What is Thunderbolt 4?

Thunderbolt 4 was launched in 2020 and builds upon the foundation of Thunderbolt 3, maintaining the 40Gbps bandwidth while introducing stricter certification requirements and a suite of enhanced features. Both standards offer the same maximum bandwidth but Thunderbolt 4 sets higher minimum performance requirements for data and video.

Thunderbolt 4 doubles the minimum video display support and PCIe data bandwidth of its predecessor. It supports two 4K displays or a single 8K display and PCIe data transfer speeds of 32 Gbps, enabling even better performance when it comes to external storage and other peripherals.

Thunderbolt 3 vs Thunderbolt 4: Key Differences

Here’s a table summarizing the key differences between Thunderbolt 3 and Thunderbolt 4:

Feature	Thunderbolt 3	Thunderbolt 4
Maximum Bandwidth	40 Gbps	40 Gbps
Minimum PCIe Bandwidth for Data	16 Gbps	32 Gbps
Minimum Video Support	One 4K display	Two 4K displays or one 8K display
Universal 40 Gbps Cables	No (varied by cable length)	Yes (up to 2 meters)
Thunderbolt Ports per Dock	Up to two	Up to four
Laptop Charging	Supported (not required)	Required for battery-powered laptops
DMA Protection	Supported (not required)	Required
Certification	Less rigorous	More rigorous

Here are some of the notable enhancements in Thunderbolt 4:

• Universal 40 Gbps speeds for all cables up to 2 meters ensure consistent performance, eliminating the variability encountered with Thunderbolt 3 cables.
• Expanded docking capabilities allow for more comprehensive solutions, with support for up to four Thunderbolt ports compared to Thunderbolt 3’s two.
• Mandatory laptop charging support ensures that battery-powered devices can be powered through the Thunderbolt port.
• Native support for Intel’s VT-d-based DMA protection enhances security by preventing physical DMA attacks.

Also worth noting is that Thunderbolt 4 cables have to go through a more rigorous certification process to ensure that they adhere to the specified standards, promoting reliability and compatibility.

Thunderbolt 3 vs 4 Key Differences: Display Support, Data Transfer Speeds, and Charging

Let’s explore the key differences between Thunderbolt 3 and 4 in more detail, focusing on display support, data transfer speeds and charging capabilities:

Display Support: Thunderbolt 4 Sets a Higher Bar

Thunderbolt 4 boasts significant improvements over Thunderbolt 3‘s display capabilities:

Higher Minimum Resolution: Thunderbolt 4 makes dual 4K displays or a single 8K display a mandatory minimum requirement for certification. Thunderbolt 3 only requires support for one 4K monitor. Some Thunderbolt 3 ports might support the higher resolutions, but it’s not a guarantee, leading to inconsistency and confusion for consumers.

Here’s a table comparing their display support capabilities:

Feature	Thunderbolt 3	Thunderbolt 4
Maximum Resolution	Two 4K displays or one 8K display	Two 4K or one 8K
Minimum Resolution	One 4K display	Two 4K or one 8K

While both technologies can handle the higher resolutions, Thunderbolt 4 makes dual 4K or single 8K support a requirement, guaranteeing that level of performance on any Thunderbolt 4 certified device. Thunderbolt 3 had inconsistency, as only some devices might have offered that, not all. This led to consumer confusion.

All in all, from a display perspective, Thunderbolt 4 enhances the user experience by setting a higher baseline for resolution support.

Data Transfer Speeds: Thunderbolt 4 Guarantees Faster Minimums

Thunderbolt 3 and 4 offer impressive data transfer speeds, but Thunderbolt 4 mandates a higher minimum. Thunderbolt 3 requires a minimum PCIe data transfer speed of 16 Gbps. Thunderbolt 4 requires a minimum PCIe data transfer speed of 32 Gbps.

While both standards offer a maximum bandwidth of 40 Gbps, Thunderbolt 4’s higher minimum data transfer speed leads to higher level of guaranteed performance with external storage and other devices.

Charging Support: Thunderbolt 4 Makes it Mandatory

Thunderbolt 4 requires laptop charging support for all battery-powered laptops, while Thunderbolt 3 only supports it but doesn’t mandate it. Both Thunderbolt 3 and Thunderbolt 4 can provide up to 100W of power delivery, ensuring compatible devices can be charged quickly and efficiently.

Feature	Thunderbolt 3	Thunderbolt 4
Laptop Charging	Supported (optional)	Required (for battery-powered laptops)
Power Delivery	Up to 100W	At least 100W

As a result, Thunderbolt 4 is the more reliable option for users who need to charge their laptops through the Thunderbolt port.

Choosing Between Thunderbolt 3 and Thunderbolt 4

Given how Thunderbolt 4 is supposed to be an improvement over Thunderbolt 3, are there any drawbacks to using Thunderbolt 4 over Thunderbolt 3?

Potential drawbacks of using Thunderbolt 4 over Thunderbolt 3

For most users, the advantages of Thunderbolt 4’s guaranteed features and better security outweigh the disadvantages. There are some relatively minor drawbacks, though:

Cost: Based on data that we’ve collected, Thunderbolt 4 cables typically cost 30% more than their Thunderbolt 3 cables of the same length. The higher certification requirements lead to increased manufacturing costs, which are then passed on to consumers. These higher certification costs also apply to Thunderbolt 4 devices as well.

Hardware Requirements: Thunderbolt 4 has stricter hardware requirements, requiring Intel CPUs with mandatory Intel controller integration. This limits vendor customization options and platform choices compared to Thunderbolt 3.

Compatibility Issues: While Thunderbolt 4 is backward compatible with Thunderbolt 3, some older Thunderbolt 3 devices may not work optimally with Thunderbolt 4 ports. Some features may be limited when using Thunderbolt 3 devices with Thunderbolt 4 ports.

Additional Considerations: The mandatory security features in Thunderbolt 4 can sometimes cause compatibility issues with older devices. The stricter certification requirements may also limit the availability of Thunderbolt 4 devices compared to Thunderbolt 3.

The advantages of Thunderbolt 4 vs Thunderbolt 3

Assuming that cost isn’t an issue, here are the advantages that Thunderbolt 4 brings:

Data Transfer: Thunderbolt 4’s higher minimum data transfer speed (32 Gbps) provides an edge for even more demanding workflows. This makes it ideal for professionals who work with large files, such as video editors, 3D modellers, and photographers.

Multiple Displays: Thunderbolt 4’s support for a minimum of two 4K displaysor one 8K display makes it a good choice for users who want to daisy-chain two screens, such as video editors, graphic designers, and gamers.

Storage Devices: Thunderbolt 4’s speed and 32 Gbps PCIe bandwidth ensures consistent high performance, making it ideal for connecting external storage devices, facilitating rapid data backups, video editing, and 3D modelling.

Security: In a corporate setting, users need to prioritize data protection. Thunderbolt 4’s native support for Intel VT-d-based DMA protection helps to thwart DMA attacks.

For better performance, security, and compatibility, Thunderbolt 4 would be the better choice. However, if you are on a limited budget or primarily use USB devices, Thunderbolt 3 would probably suffice.

Final Thoughts – Thunderbolt 3 vs 4

Thunderbolt technology has been quite the gamechanger for connecting and powering multiple devices. While the performance improvements in Thunderbolt 4 may not seem revolutionary compared to Thunderbolt 3, there’s a noticeable improvement and stricter standards around PCIe bandwidth, display support, ports per dock and charging.