PCI Express x16 GPUs Video Graphics Cards

PCIE x8 slot, and the 3080 should be ok running on a PCIE x16 slot In practice, I would question if your Bios

Systems with PCI Express ® Slot Spec Revision PCIe at 32GTs PCIe Ash Creek Falls Driving, PCIe at 8GTs, x16, Processor Root Complex

pcie 3 slot Supports 7th Generation Intel® Core™ Processor; Intel B250 single chip architecture; Support 2-DIMM DDR4-2400 2133 1866 up to 32G maximum capacity

pciex4 slot  5GTs or 500MBs 8GTs or 1GBs 16GTs or 2GBs The Notice that the PCIe x16 slot has a retention lever