PCIe

PCIe is the high-speed serial expansion bus standard used to connect GPUs, NVMe SSDs, and network controllers directly to the CPU.

Peripheral Component Interconnect Express (PCIe) serves as the primary data highway for modern computing hardware. It utilizes point-to-point topologies and dedicated lanes (typically x1, x4, x8, or x16) to deliver massive bandwidth with low latency. The current PCIe 5.0 specification provides 32 GT/s per lane, enabling a full x16 slot to push 128 GB/s of bidirectional throughput. By employing a layered protocol stack and differential signaling, PCIe ensures backward compatibility across generations while powering everything from enterprise-grade AI accelerators like the NVIDIA H100 to consumer-grade M.2 storage devices.

https://pcisig.com