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PCIe

The high-speed slot standard that connects graphics cards and NVMe drives to the CPU.

PCIe PCIe expansion slots come in lane lengths like x1, x4 and x16, and in generations; a newer card in an older slot still works, running at the older slot's speed. Slot lengths = lanes (more lanes, more bandwidth) x1 x4 x16 (graphics card slot) Generations are compatible both ways Gen5 card newer device into Gen4 slot older board Works, at the slower Gen4 speed

The high-speed expansion bus that links graphics cards, NVMe SSDs and other add-in cards to the CPU and motherboard. Slots and links come in lane counts (x1, x4, x8, x16) and in generations (Gen3, Gen4, Gen5), where each newer generation roughly doubles the bandwidth per lane. PCIe is backward- and forward-compatible: a newer card works in an older slot and vice versa, automatically running at whichever device's generation is lower.

Concrete example

a Gen5 graphics card in a Gen4 slot still works, just at Gen4 speeds.

What it means when you're buying

you rarely need to chase the newest PCIe generation for gaming, since current GPUs barely saturate even Gen4 x16 — focus instead on having enough x16 and M.2 slots for the cards and drives you actually plan to install.

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