What is the PCIEX16 reading?

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Pcie x16 slot into multiple x4 slots · PCIE Bifurcation · IBM 69Y5321 M4 PCIe Gen-III Riser Card 2 · Cablem ATIC

pciex16 slot configuration MSI afterburner says my GPU temp is 30 I'm quite confused When I googled PCIEX16 results are referring to PCI-e x16 slot of the motherboard

spinsane slot pcie x16 slot, pcie x1 slot, pcie x4 slot, pcie x8 slot, which pcie slot to use, does it matter which