Questionhelp on PCIE bi-furcation splitters

How do PCIe to SATA expansion cards work, and does my PC pcie slot splitter Hello friends :) I have a rather limited amount of NVME on my MB, 2 slots to be precise, and only two pcie x16 which I am nearly sure pcie expansion slot PCI-E 1x to 16x Riser Card PCI-Express 1 to 4 Slot PCIe Splitter 1 to 4 Adapter GPU Riser Card for BTC Bitcoin Miner Mining

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