vram in the context of an igpu like an apple chip or strix halo is the same thing as system ram. its shared memory

its why strix halo and apple m4 chips are popular with users running local ai models, because those will cost you 2-4000$ for 128 gb ram, while the closest nvidia alternative is the RTX 6000 blackwell with 96gb vram costing 2-4x more.