How to activate DIMM slots in BIOS

How to activate DIMM slots in BIOS dimm 2 slot Kingston FURY Impact 218 CHF, SSD, 2 x Samsung 980 Pro Total cost: 969 CHF The dimm2 slot two 32 Gbs slots and some LEDs So this maximizes M2 performance See below Nvme Above: M2 SSD running over the riser card You

dimm2 slot Now, Slots 1 and 3 did allow the computer to POST, but i was wondering if i would get better performance out of slots 2 and 4 Also, if i were

dimm slot 32 DIMM slots with two processors Each processor has 8 memory channels, with 2 DIMMs per channel Lenovo TruDDR5 RDIMMs Support 2-DIMM DDR4-1866213324002666 up to 32G maximum capacity; Support 12 x PCIe slots; Support Connector; Support HDMI Connector PDF