In the ever-evolving world of connectivity, Thunderbolt has emerged as a powerhouse, revolutionizing how we connect devices to our computers. With the introduction of Thunderbolt 4, many users find themselves wondering: what sets it apart from Thunderbolt 3? In this comprehensive guide, we’ll break down the key differences, similarities, and practical implications of these two cutting-edge technologies.
A Brief Overview: What is Thunderbolt?
Before diving into the comparisons, let’s recap what Thunderbolt is. Developed by Intel in collaboration with Apple, Thunderbolt is a high-speed connectivity standard that combines data transfer, video output, and power delivery into a single, compact port. It uses the USB-C physical connector, making it versatile and widely compatible with various devices.
Key Differences Between Thunderbolt 3 and Thunderbolt 4
While Thunderbolt 3 and 4 share some core features, several critical upgrades in Thunderbolt 4 make it a more robust option. Let’s explore these differences in detail:
1. Bandwidth and Data Transfer Speed
At first glance, both standards advertise a maximum data transfer speed of 40 Gbps—but there’s a catch.
- Thunderbolt 3: While it supports 40 Gbps, some implementations (especially in lower-cost devices) may only offer 20 Gbps due to relaxed certification requirements. This can lead to inconsistent performance across devices.
- Thunderbolt 4: Intel tightened the specifications, requiring all Thunderbolt 4 devices to support the full 40 Gbps bandwidth. This guarantees consistent speed across all certified products.
2. Video Output Capabilities
For users who connect multiple monitors or high-resolution displays, video output is a key consideration:
- Thunderbolt 3: Supports up to two 4K displays (3840×2160) at 60Hz or one 5K display (5120×2880) at 60Hz.
- Thunderbolt 4: Ups the ante by supporting up to two 4K displays ou one 8K display (7680×4320) at 60Hz. This makes it ideal for professional workflows involving ultra-high-definition content.
3. Power Delivery (PD)
Power delivery determines how much a Thunderbolt port can charge connected devices:
- Thunderbolt 3: Typically offers up to 100W of power, which is sufficient for charging laptops, smartphones, and small peripherals.
- Thunderbolt 4: Maintains the 100W maximum but includes more efficient power management, ensuring stable charging even when multiple devices are connected.
4. Security Features
Thunderbolt 4 introduces enhanced security measures:
- Thunderbolt 3: Relies on optional security protocols, which may not be enabled by default on all devices.
- Thunderbolt 4: Mandates support for Intel VT-d (Virtualization Technology for Directed I/O), which protects against physical DMA (Direct Memory Access) attacks. This is a critical upgrade for enterprise and government users handling sensitive data.
5. Compatibility and Daisy-Chaining
Both standards support daisy-chaining (connecting multiple devices in a sequence), but Thunderbolt 4 improves flexibility:
- Thunderbolt 3: Allows up to 6 devices in a daisy chain, but the total bandwidth is shared across all connected devices.
- Thunderbolt 4: Supports up to 4 devices in a daisy chain but guarantees that each device gets the full 40 Gbps bandwidth when needed. This reduces bottlenecks in complex setups.
Side-by-Side Comparison Table
Fonctionnalité | Thunderbolt 3 | Thunderbolt 4 |
Max Data Transfer Speed | Up to 40 Gbps (varies) | 40 Gbps (guaranteed) |
Sortie vidéo | 2x 4K or 1x 5K at 60Hz | 2x 4K ou 1x 8K à 60Hz |
Fourniture d'énergie | Up to 100W | Up to 100W (improved efficiency) |
Sécurité | Optional protocols | Mandatory Intel VT-d |
Daisy-Chaining | Up to 6 devices | Up to 4 devices (full bandwidth) |
Minimum Requirements | Relaxed (some 20 Gbps devices) | Strict (40 Gbps required) |
Lequel choisir ?
- Choose Thunderbolt 3 if: You’re on a budget, use basic peripherals (e.g., external hard drives, 4K monitors), and don’t need advanced security or 8K support. Many older laptops and desktops still feature Thunderbolt 3, and it remains a reliable choice for everyday use.
- Choose Thunderbolt 4 if: You work with high-resolution media (8K video, 3D rendering), need secure connections, or use multiple devices in a daisy chain. It’s also future-proof, as more 8K displays and high-performance peripherals hit the market.
Conclusion
Thunderbolt 4 builds on the strengths of Thunderbolt 3 with stricter standards, improved video output, enhanced security, and consistent performance. While Thunderbolt 3 is still capable for most users, Thunderbolt 4 is the clear choice for professionals and anyone looking to invest in long-term connectivity.
As technology advances, Thunderbolt continues to set the bar for high-speed, versatile connectivity—whether you’re a content creator, gamer, or office user, understanding these differences will help you make informed decisions about your devices and peripherals.
