Originally Posted by ozlay
Why not use IF to connect the chipset to the CPU? Instead of using pcie Lanes.
Backwards compatibility with X370/X470 probably. The reduced complexity of the IO/chipset dies would make it cheaper to produce as well.
The same can be asked of why Navi can not use IF to link to Ryzen 3 when they use it in Vega II Duo (84GB/s bi-directional link on that one btw).