A few miscellaneous PCIe questions
A few miscellaneous PCIe questions
This is my initial visit to the forum, so please understand I might not ask the right questions. I'm a passionate hardware enthusiast and am diving deeper into the details of hardware. Right now, my focus is on PCIe technology. While much has been learned online, I have some precise queries that require expert insight, so I hope this helps.
1) Why do PCIe lanes have multiple pins? It seems like one pin per lane would suffice, plus a few for power and other functions. Why the extra pins?
2) What is the purpose of the notch placement? I imagine it could help align cards or ensure proper orientation. Does it serve a specific function beyond just fitting the card?
Thank you in advance for any guidance. I find this topic fascinating and just want to understand better. If you have any recommendations or references, that would be really appreciated!
PCIe relies on differential pairs for data transfer, meaning two pins per signal. Being full duplex means each lane contains a pair of signals—one for sending and one for receiving—resulting in four pins per lane. https://en.wikipedia.org/wiki/PCI_Express#Lane The notch distinguishes power/control from main data, though the exact purpose seems more like a design convenience.