Support GPU?

Hello,
I noticed the Star64 board support PCIe x1 Slot.
I want to power-on Star64 with uboot(or UEFI/EDK2) ,so,does uboot(or UEFI/EDK2) support PCIe GPU(such as AMD graphics-card or nvidia graphics-card )?

PCIE external GPU is supported.

Hello,

It looks like OS gpu.So does uboot(or UEFI/EDK2) support??