A 10W Raspberry Pi 4 And A 230W RX 6700 XT
This project over at Hackaday shows just how flexible the Raspberry Pi is, as long as you are willing to put in a bit of work. Using the Raspberry Pi compute module, which includes a single PCI-e slot with a single PCIe lane and powering both the GPU and the Raspberry Pi with an ATX PSU Jeff Geerling was able to get the two pieces of hardware to talk to each other.
The Raspberry Pi 4 has a different ground plane, which means he needed to use an adapter to ensure both devices were receiving clean power, which he succeeded at. As well he needed a PCIe adapter to connect the x16 GPU to the x1 PCIe slot so that the compute unit and RX 6700 XT could communicate.
Jeff installed a custom version of Linux and attempted to compile a kernel using AMD’s Linux drivers, which did not go so well, but for reasons he believes he can resolve. He is detailing his work on resolving issues including running out of memory space for the Pi through to PSP memory training for the GPU however the bottom line is they are communicating.
You won’t be playing Crysis on this any time soon, but for compute heavy tasks it will greatly enhance the ability of the Raspberry Compute module and teach you a lot about the PCIe bus, memory allocation and the technical capabilities of the Raspberry Pi 4.