Mac Pro comes preinstalled with the Apple I/O card in slot 7, which contains a 3.5 mm headphone jack with support for high-impedence headphones, two HDMI ports, and two USB-A ports.

If you ever looked at a PCI to PCIe x16 adapter and wondered what’d happen if you were to stick a modern PCIe GPU in it, the answer apparently is ‘it works’ according to an attemp… ...