Thunderbolt · 2015
Thunderbolt 3
The first Thunderbolt on USB-C. 40 Gbps, but with optional minimums that make ports differ.
- data: 40 Gbps (PCIe 16–32 Gbps)
- video: two 4K 60 Hz
- power: up to 100 W (USB PD)
Spec card
- Link rate
- 40 Gbit/s (2 lanes × 20)
- PCIe tunnel
- minimum 16 Gbit/s; 32 Gbit/s on many ports
- Displays
- two 4K 60 Hz (DisplayPort 1.2 streams on most controllers)
- Bus power
- 15 W for accessories
- Charging
- USB PD up to 100 W
- Passive cables
- 40 Gbps up to 0.5 m; 20 Gbps up to 2 m
- Active cables
- 40 Gbps up to 2 m
Also sold as TB3
The cable you need
A Thunderbolt 3 cable with "40" by the logo, or any Thunderbolt 4 cable.
Watch out for
- Thunderbolt 3 cables longer than 0.5 m without a "40" mark run at 20 Gbps.
- Some early active Thunderbolt 3 cables don't carry USB 3 data at all.
- A Thunderbolt 3 laptop may support only one external display.
Thunderbolt 3 moved Thunderbolt to the USB-C plug and runs a 40 Gbps link that tunnels PCIe and DisplayPort. It is why one cable to a dock can carry two monitors, Ethernet, USB and charging.
The trouble is that Intel's minimums for Thunderbolt 3 were low. A laptop could ship with only 16 Gbps of PCIe or support just one external display and still carry the logo. Thunderbolt 4 closed those gaps.
Cables matter too. Passive Thunderbolt 3 cables longer than 0.5 m usually run at 20 Gbps. Look for the number "40" printed under the lightning-bolt logo. Older active Thunderbolt 3 cables carry 40 Gbps over 2 m, but some of them don't carry ordinary USB 3 data.
What it can carry
Computed from each link's usable bandwidth; 4K at 60 Hz and above assumes 10-bit HDR colour. How.
| Mode | Thunderbolt 4 |
|---|---|
| 1080p 60 Hz 8-bit | Fits 3.2 Gbps |
| 1080p 144 Hz 8-bit | Fits 8.0 Gbps |
| 1440p 144 Hz 8-bit | Fits 14.1 Gbps |
| 4K 30 Hz 8-bit | Fits 6.2 Gbps |
| 4K 60 Hz 10-bit | Fits 15.7 Gbps |
| 4K 120 Hz 10-bit | With DSC 32.3 Gbps |
| 4K 144 Hz 10-bit | With DSC 39.2 Gbps |
| 4K 240 Hz 10-bit | With DSC 68.6 Gbps |
| 8K 60 Hz 10-bit | With DSC 62.1 Gbps |