How to check PCI type and version of free PCI slot in Linux shell

What is a PCIe SSD? pci e slot is a form factor, there are a few variants for different applications, but the variant we are interested in for NVME SSDs is M key This pciex4 slot When I was young, I used a software called everest to check the hardwares and most of the time, it could tell me tons of information Seems it

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