i have seen some boards where NVMe M.2 cards do sacrifice available PCIe bandwidth or entire slots even, and others where SATA M.2 cards sacrifice available SATA ports.
i would just guess/hope that a $400+ higher end board would not require these sacrifices considering the large usage of M.2 these days.
hopefully you can determine that it is just a BIOS setting that's needs changing or something similar.
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