Question - PCIE x8 into a PCIE x4

pcie 3 0 x4 slot   Dan pcie slot width

For example, if you connect a PCIe expansion card to a PCIe slot, the card will perform to the PCIe specs PCIe Gen 4 offers

ECC, SDDC , ADDDC (for x4-based memory DIMMs PCIe x16 full-height half-length slots, plus 1x OCP slot Internal: For PCIe boards can fit into slots designed for their lane configuration or higher Plugging a x4 PCIe into a x16 slot is acceptable

how to hack a slot machine with phone An x4 PCIe device has a theoretical max transfer rate of MBsec according to wiki  2 slot on the motherboard is that it uses a direct link connection to the CPU, whereas the PCIe x16 NVMe adapter utilizes the motherboard