It handles the flow of data packets. It ensures that a "Read" request from the CPU reaches the correct SSD and that the "Data" packet finds its way back.
How to find your Root Complex settings in or Linux lspci pci express root complex
Modern CPUs often have "dedicated" PCIe lanes (typically 16 or 20) that go straight to the primary GPU and M.2 slots, managed by the on-chip Root Complex. Summary 💡 It handles the flow of data packets
The transition of the Root Complex from a separate chip to an integrated part of the CPU (System on a Chip or SoC) changed everything. Summary 💡 The transition of the Root Complex
Bugs in UEFI/BIOS initialization can cause lane negotiation failures, reduced speeds (e.g., GPU running at PCIe 3.0 instead of 5.0), or broken hot-plug. This isn’t the RC’s fault, but you’ll blame it anyway.