Forward-looking: Thunderbolt 5 doubles Thunderbolt 4's bandwidth, offering 80Gbps transfer speeds in either direction. However, Thunderbolt 5's alternate mode can transmit at 120Gbps while receiving data at 40Gbps upon detecting certain devices. The extra boost currently only supports cable lengths up to two meters.
In context: For those unfamiliar with OCuLink, it is an optical interface developed over a decade ago, primarily for servers. However, it has recently gained attention for consumer uses, such as external GPUs. OCuLink offers higher bandwidth compared to Thunderbolt 4 – up to 64 Gbps versus 40 Gbps. This increased bandwidth opens up the possibility better eGPU performance compared to Thunderbolt.