Thunderbolt 4: Advantages and Disadvantages

This page explores the pros and cons of the Thunderbolt 4 interface.

Introduction:

The Thunderbolt interface has revolutionized how we connect laptops and desktops to high-performance storage, displays, and multimedia devices, all through a single cable. It leverages both PCIe and DisplayPort protocols and supports power delivery over the cable. It also allows daisy-chaining up to 6 devices. Different generations of Thunderbolt exist, including Thunderbolt 1, 2, 3, and the latest, Thunderbolt 4, each with varying speeds and features.

What is Thunderbolt 4?

Thunderbolt 4 is backward compatible with previous versions, delivering a robust 40 Gbps speed for transferring video, data, and power over a single cable.

Thunderbolt 4 has these requirements:

• One universal computer port
• Universal 40 Gb/s cables up to 2 meters in length.
• Supports two 4K displays (instead of just one) or a single 8K display.
• Accessories with four Thunderbolt ports
• Required PC charging on at least one computer port
• Required PC wake from sleep when connected to a Thunderbolt dock
• Thunderbolt networking (10 Gbps ethernet connection between PCs)
• Mandatory certification for all shipping computers, accessories, and cables
• Cable testing and cable quality audits for Thunderbolt cable manufacturers
• Required Intel VT-d based DMA protection

Benefits (Advantages) of Thunderbolt 4

Here are the advantages of Thunderbolt 4:

• It supports docks with up to four Thunderbolt ports and universal cables up to 2 meters in length.
• It’s compatible with the vast ecosystem of PCs and accessories that comply with Thunderbolt 3.
• It offers increased performance compared to previous Thunderbolt versions.
• It adheres to the USB4 Specification, transmitting data, video, and power through a single USB Type-C port at 40 Gbps.
• It enables power savings by allowing users to wake their computers from sleep simply by touching a keyboard or mouse when connected to a dock.
• Laptops with Thunderbolt 4 can accept input power up to 100 Watts and can supply 15 Watts externally.

Limitations (Disadvantages) of Thunderbolt 4

Here are the limitations of Thunderbolt 4:

• It supports fewer devices in daisy-chaining (around 6) compared to USB (around 127) and Firewire (around 63).
• Devices supporting Thunderbolt 4 tend to be more expensive than USB alternatives.
• Laptop vendors must support Intel VT-d based DMA (direct memory access). VT-d is a security measure that protects the system by preventing DMA to pre-assigned domains. This can potentially create issues with manufacturers like AMD.

Conclusion

While Thunderbolt 4 shares the same speed as Thunderbolt 3, it offers numerous improvements and benefits over its predecessors.