What is PCIe? A 60 Second Overview

Our blog post about PCIe 4.0 has been very popular, likely because this connectivity standard has become the go-to interface for so many of today’s expansion cards and GPUs. That post largely focuses on the differences between generation 3.0 and 4.0. But what is PCIe exactly?

In our Tech Edge video below, we break down the basics of PCIe in just 60 seconds. Check out the video, and be sure to subscribe to the OnLogic YouTube channel for more.

What is PCIe?

PCIe stands for Peripheral Component Interconnect Express. It’s the term for a particular type of connection between a computer’s motherboard (or host) and peripherals (or endpoints) like graphics cards, sound cards, solid state drives, and expansion cards. To connect them, you plug the PCIe card into the PCIe slot on the board.

Types of slots and cards

There are 5 common types of PCIe slots and cards: x1, x2, x4, x8, and x16. The numbers represent the number of lanes on the card or slot. Just like the lanes on a road, these lanes are paths for data to travel on. X1 has just one lane, x4 has 4 lanes, etc. The more lanes, the more data can travel on them, and therefore the higher the potential rate of data transfer.

What are PCIe generations?

Five generations of the PCIe standard have been established. The key difference between them is that the data transfer rate in each individual lane has doubled with each new generation. The newest available generation is 5.0 and it offers up to 32 gigatransfers per second per lane. 

Although the PCI-SIG announced the release of the specification for PCIe 6.0 in January of 2022, it will likely take years for PCIe 6.0 to become available on commercial products.

What other PCIe questions do you have?

Ready to explore more? Check out our variety of expansion cards and add-on modules for flexible I/O including daughterboards, PCI, PCI Express, and PCI Express Mini Cards. If you still have questions, reach out to our team of experts.

This blog was originally posted on April 14th, 2021. It was updated for content on August 20th, 2022.