NVIDIA has a fantastic reference guide for high-bandwidth cables and connectors: NVIDIA Cable Management Guidelines and FAQ.
Of note,
| Transceiver | Signals | Applications |
|---|---|---|
| QSFP56 | 4x50G | HDR InfiniBand 200G/400G Ethernet |
| QSFP-DD | 8x25G (NRZ) 8x50G (PAM4) | 200G Ethernet Slingshot |
| OSFP | 8x25 8x50 8x100 | NDR InfiniBand |