All PCI Express (PCIe) types explained
PCI Express (PCIe) is the high-speed interface that connects hardware directly to your CPU—including graphics cards, NVMe SSDs, network cards, and sound cards. The core philosophy of PCIe is simple: every new generation doubles the speed (bandwidth) of the previous one while maintaining 100% backward compatibility. 1. PCIe Speeds Across Generations PCIe bandwidth depends on generation and lane width (written as x1, x4, x8, or x16). Below are the theoretical maximum speeds (one direction) for every major PCIe generation. Generation Launch Raw Data Rate Encoding x1 (1 Lane) x4 (M.2 NVMe SSDs) x16 (GPUs) PCIe 1.0 2003 2.5 GT/s 8b/10b 250 MB/s 1 GB/s 4 GB/s PCIe 2.0 2007 5.0 GT/s 8b/10b 500 MB/s 2 GB/s 8 GB/s PCIe 3.0 2010 8.0 GT/s 128b/130b ~1 GB/s ~4 GB/s ~16 GB/s PCIe 4.0 2017 16.0 GT/s 128b/130b ~2 GB/s ~8 GB/s ~32 GB/s PCIe 5.0 2019 32.0 GT/s 128b/130b ~4 GB/s ~16 GB/s ~64 GB/s PCIe 6.0 2022 64.0 GT/s PAM4 + FLIT ~8 GB/s ~32 GB/s ~128 GB/s PCIe 7.0 2025 128.0 GT/s PAM4 +...