> PCIe Gen 3 and SATA are still pretty new...

That's an interesting thought to look at. PCIe 3 was a while ago, but SATA was nearly a decade before that.

> I wonder what modulation order / RF bandwidth they'll be using on the PHY for Gen8. I think Gen7 used 32GHz, which is ridiculously high.

Wikipedia says it's planned to be PAM4 just like 6 and 7.

Gen 5 and 6 were 32 gigabaud. If 8 is PAM4 it'll be 128 gigabaud...