I hopefully will be upgrading to a system with a 5800x CPU later this month or within the 1st half of next month. I plan on have a 980 Pro 250GB NVMe as a dedicated OS drive to replace my 860 EVO 250GB SATA SSD, and then later on a 980 Pro 2TB NVMe (not yet released) as a Games/Data drive (currently using a 850 EVO 2TB SATA SSD). I understand that the B550 motherboards only support PCIe 4.0 on the 1st NVMe slot (closest to the CPU) and the lower NVMe slot is run via the chipset lanes at PCIe 3.0. Is it worth getting an X570 motherboard over a B550 one if I'm going to use a 2nd NVMe drive for just the Windows 10 operating system plus a few basic programs such as Libre Office, Photoshop, and the Steam launcher? Is the OS disk duties of Windows 10 really sequential bandwidth intensive that it will benefit from PCIe 4.0 over PCIe 3.0 or random access time way more important than sequential transfer rates for an OS drive?