External GPU (eGPU) enclosures use Thunderbolt 3 or Thunderbolt 4 USB-C for PCIe x4 connectivity to laptops, providing up to 22 Gbps PCIe bandwidth for discrete GPU performance in portable systems.
| Pin | Name | Function | Type |
|---|---|---|---|
| 1 | GND | Ground | GND |
| 2 | TX1+ | Thunderbolt PCIe TX1 positive | BUS |
| 3 | TX1- | Thunderbolt PCIe TX1 negative | BUS |
| 4 | VBUS | 5V USB power | PWR |
| 5 | CC1 | Thunderbolt configuration | BUS |
| 6 | RX2+ | Thunderbolt PCIe RX2 positive | BUS |
| 7 | RX2- | Thunderbolt PCIe RX2 negative | BUS |
| 12 | GND | Ground | GND |
External GPU (eGPU) enclosures use Thunderbolt 3 or Thunderbolt 4 USB-C for PCIe x4 connectivity to laptops, providing up to 22 Gbps PCIe bandwidth for discrete GPU performance in portable systems.