pcie x16 slot ✓ USB PCIe card in x16 slot?

I'm getting the error One additional PCIe x16 slot is needed I'm only looking to use a single PCIe slot, so I don't understand why it's saying one is needed pcie x16 slot,In the AMD Radeon Software, the GPU is set at PCIe x8 but it's inserted into the PCIe x16 slot Is there any correlation with the Ryzen 7

SuperSpeed Storage：PCIe x4 Connector; EZ-Latch：PCIe x16 Slot with Quick Release Design; Fast Networks：GbE LAN; Extended Connectivity：DP, HDMI; Smart pcie x16 slot,Mainly there are more than 1 x16 slots for the sole purpose of Multi-GPU scaling, well, that's dead in 2020s standards

pcie x16 slot,First, here are a few troubleshooting steps to determine if the problem is with the PCIe card or the PC