motherboard - Is PCI Express x4 faster or slower than a standard ...
Does a Graphics Card Have to Go in the First PCI-E Slot?. You may have wondered which slot you're supposed to install a graphics card into on a motherboard when there's more than one slot.
Mainboard Gigabyte Z790 D DDR5
* The PCIEX16 slot can only support a graphics card or an NVMe SSD. If only one graphics card is to be installed, be sure to install it in the PCIEX16 slot. – ...
Express Card Slot Graphics Card - ms.codes
Yes, you can use an external display with a graphics card installed in an Express Card slot. Once the graphics card is installed and the necessary drivers are installed, you can connect an external display to the graphics card's video outputs.