Why do internal > external SAS expanders require a PCIe slot?

ROG Srix Z390-i Gaming 1 Long Beep and 3 short How do I fix this? short pcie slot What is PCIe or PCI Express? PCIe is short for “peripheral component interconnect express” and it's primarily used as a standardized short pcie slot Am i meant to priseremove what looks like a cover with the Gigabyte logo on it? or is the mobo designed for a short PCIe card? Please see the attached to

millenium slot My motherboard has three pcie x16 size slots, but I cannot use one of them for usb controller pcie x4 card: the pcie16_1 is for GPU, the