Motherboard pci express x16 slot specification details explained in

Yes, a x1 card should work in a x16 slot It's good that you've got it to work in a x1 slot What else have you tried it in besides the x16 slot

List of Motherboards with 3 PCI-Express x16 Slots: GIGABYTE B650 Gaming X AX V2, MSI X670E Gaming Plus WiFi, ASUS ROG Strix Z790-E Gaming WiFi II,

x16 slot On the motherboard, PCIe lanes appear in x1, x2, x4, x8, and x16 variations More lanes mean more bandwidth, as well as a longer slot GPUs are usually

neko slot - 1 x PCI Express x16 Slot * - 1 x PCI Express x16 Slot AMD Ryzen series CPUs