is the high-speed serial computer expansion bus standard that serves as the primary communication link between a computer's central processing unit (CPU) and high-performance peripherals like graphics cards and SSDs. Developed and maintained by the PCI-SIG (PCI Special Interest Group), these specifications define the physical and logical layers required to ensure interoperability and massive data throughput across modern computing ecosystems. Core Architecture and Physical Specifications
Do you have a specific question about PCIe or would you like to know more about a particular aspect of the specification? pcie specifications
PCI-SIG is finalizing electrical specs, but the next frontier is optical PCIe (expected around 2026–2027). This will: is the high-speed serial computer expansion bus standard
| Generation | Year | Transfer Rate (per lane) | Bandwidth (x16 lane) | Encoding Overhead | | :--- | :--- | :--- | :--- | :--- | | | 2003 | 2.5 GT/s | 4 GB/s (8 GB/s bidirectional) | 8b/10b | | Gen 2.0 | 2007 | 5.0 GT/s | 8 GB/s (16 GB/s bi-di) | 8b/10b | | Gen 3.0 | 2010 | 8.0 GT/s | 16 GB/s (32 GB/s bi-di) | 128b/130b | | Gen 4.0 | 2017 | 16.0 GT/s | 32 GB/s (64 GB/s bi-di) | 128b/130b | | Gen 5.0 | 2019 | 32.0 GT/s | 64 GB/s (128 GB/s bi-di) | 128b/130b | | Gen 6.0 | 2022 | 64.0 GT/s | 128 GB/s (256 GB/s bi-di) | 1b/1b (PAM4 + FLIT) | | Gen 7.0 | Draft (2025) | 128.0 GT/s | 256 GB/s (512 GB/s bi-di) | 1b/1b (PAM4 + FLIT) | PCI-SIG is finalizing electrical specs, but the next
According to a review by Tom's Hardware, the PCIe 4.0 interface provides a significant boost in performance for NVMe storage devices, with sequential read and write speeds reaching up to 7000 MB/s and 5000 MB/s, respectively.