(FIXED) SN850 1TB NVME - slow write speeds (3100) on x570 using M2 Chipset slots (PCH) - confirmed as a problem on MSI, ASRock, Gigabyte and Asus motherboards

Would be good to hear what MSI have to say, here is what Asrock told me for same issue of slow write speeds with SN850 on X570 chipset lanes: