1050ti GPU only lines up with pcie x4 slot - what will happen?

My mobo manual says that the x16 slot is for a GPU, but more googling has revealed that others have plugged a x1 raid controller in the slot

If you have the option of multiple slots where at least one supports PCIe, it's worth considering your secondary slot for an SSD upgrade When combined with

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spirited wonders slot However, the 2nd PCIe x16 slot works at PCIe x4 if two GPU are connected means the primary PCIe x16 slot gets 16 lanes and I still have 4 lanes