Tech-YouTuber Level1Techs received a prototype custom B650 LiveMixer motherboard from ASRock. By adding a connector, the X670 Xpansion Kit can be placed in the lower pcie slot. This adds a Promontory21 chipset to the motherboard, extending the functionality to that of X670. A standard X670 board also contains two of these B650 chipsets. The card offers two additional PCIe 4.0 m.2 slots, three USB-A, USB Type-C 10Gb, two Sat…