Ok thanks for all theses advices, actually there are 8 x DIMM, Max. 128GB, DDR4 on my ASUS ROG STRIX X399E, so what you mean is putting 2 X on one channel and 2 on the other one, that's what you mean with "spreading" my DIMM ?
yes maybe my CPU has degraded but for now i reseted my BIOS to...