MSI Z790-P WIFI DIMM Slot issue?

DIMM 3 and DIMM 4 RAM slots won't work dimm 2 slot ASUS ROG Maximus IX Apex Z270 slot ASUS ROG Maximus IX Apex Z270 uses a slot The motherboard doesn't have any slots on it interesting dimm slot Supports 4-DIMM DDR4- 1866 2133 2400 2666 2800 2933 3200 3600 Supports PCIe ; Supports HDMI 4K2K; Supports USB Gen1

dimm 2 slot DIMM slots of the same colour indicate different channels In the figure, DIMM1 and DIMM3 are on channel A, whereas DIMM2 and DIMM4 are on