[cpgxiii]

There's at least one m.2 GPU based on the Silicon Motion SM750 controller made by Asrock Rack. Similar products exist for mPCIe form factor.

Performance is nowhere near a modern iGPU, because an iGPU has access to all of the system memory and caches and power budget, and a simple m.2 device has node of that. Even low-end PCIe GPUs (single slot, half-length/half-height) struggle to outperform better iGPUs and really only make sense when you have to use them for basic display functionality.