2 NVMe SSD's which slot to put OS on and does it matter?

does it matter which m 2 slot i use   Dan does slot open on sundays

I should note that this used to occur when I used my HDD to download larger game files as my SATA is only 256GB Some potentially relevant

SATA is just a complete wasted slot ; all slots should be dual NVMESATA capable, or Supports AMD Socket AM5 Ryzen™ 9000, 8000 and 7000 Series Processors; 8+2+1 Power Phase, ; 2 x DDR5 DIMMs, Supports Dual Channel, up to 7200+ ;

dmz second insured slot Two slots, M2_2 and M2_3, are connected to the CPU This might require physical inspection to determine which is which You could perhaps take If you want the best performance, put it in the CPU slot Otherwise it doesn't matter Also putting it in the CPU slot doesn't affect the PCIe