PCI Lane Calculator

Use this tool to calculate the transfer rate per lane in Megabytes per second or Gigabytes per second.

Calculator

Enter

• Transfer Rate
• Encoding scheme (select one of two options)
• Number of lanes

The tool provides the raw transfer rate per lane and for all lanes combined

Example Calculation

For a transfer rate of 16 GT/s (PCIe version 4.0), and 128b/130b encoding, the calculator gives the throughput value of 1.969 GB/s per lane. For 16 lanes this gives 31.508 GB/s.

Background

To calculate the transfer rate of a PCI Express (PCIe) connection, you need to know the following

1. Transfer rate
2. Number of lanes: Min 1 and Max 16. This indicates how many parallel paths of communication are available.
3. Encoding overhead: PCIe uses an 8b/10b encoding scheme for versions 1.x and 2.x (which introduces a 20% overhead). A more efficient 128b/130b scheme is used for versions 3.0 and above (1.5% overhead). Version 6.0 and higher uses the most efficient 1b/1b scheme.

Use the PCIe bandwidth calculator to find the transfer time depending on the number of lanes and version number.

Wikipedia References

• Peripheral Component Interconnect Express PCIe
• Peripheral Component Interconnect PCI

Related Posts

• Memory Bandwidth
• RAM Latency
• MBps vs Mbps – what’s the difference?
• Mbps to Gbps
• Megabyte per second to Gigabyte per second