Much is known about Z690 motherboards, less so for B650, the budget alternative. As it looks now, the more affordable motherboards will not be supporting PCIe Gen 5.0, which really isn't that weird at all considering you'll still get PCIe Gen 4.0 slots.

Where does this info originate from, well a review received a B650 motherboard accidentally and noticed the new configurations. Several photographs of the product packaging were sent to colleague website VideoCardz by the reviewer, one of which clearly shows a label stating PCIe 4.0 capabilities.

Intel 12th Generation Alder Lake processors contain attached PCIe 5.0 lanes that are distinct from the chipset, this has come as a surprise to many people. In light of the fact that the B660 chipset is intended for the mid-range market, the lack of PCIe 5.0 capability on this specific motherboard could be considered a cost-cutting or artificial separation tactic. Of course, nothing is certain until released.

Intel B660 Motherboards Could Lack PCIe 5.0 Support