Depending on the chip, they have somewhere from 100 to 400 GB/s. I’m not sure on the numbers on Intel processors. I think the consumer processors have about 50 - 80 GB/s. (~Alder Lake, dual channel DDR5) Mine seems to have way less. And a recent GPU will be somewhere in the range of 400 to 1000 GB/s. But consumer graphics cards stop at 24GB of VRAM and these flagship models are super expensive. Even compared to Apple products.

The people from the llama.cpp project did some measurements and I believe the Apple “Metal” framework seems to outperform the x86 computers by an order of magnitude or so. I’m not sure, it’s been some time since i skimmed the discussions on their Github page.