What are the top uses of PCIe x1 Slots?

The 3rd Gen PCIe x1 slots have 1Gbps of data transfer speed and can handle multiple SATA expansion with SATA SSD or SATA

Other PCIE slots are x16 physically, but they all operate as x1 electrically With that said, if I put my HBA to the x1 slot, what is

pcie slot x16 The PCIe x1 Graphics Card is a powerful and versatile piece of technology that has revolutionized the world of computer graphics

pcie 4 m2 in pcie 3 slot PCIe Gen 3 was unable to accommodate the full bandwidth of high-speed PCIe NVMe SSDs This was effectively creating a bottleneck in SSD performance PCIe Gen 4