The ASUS Hyper M.2 X16 card is not a direct replacement for the QNAP QM2-2P-244A card in a QNAP TS-453D NAS. This is because the ASUS card is an M.2 PCIe x16 memory controller supporting up to 4 M.2 disks in RAID, while the QNAP QM2-2P-244A card is specifically designed for QNAP NAS with features and hardware compatibility adapted to this model. The TS-453D does not have a standard PCIe x16 slot to accommodate this ASUS card, and hardware and software compatibility would not be guaranteed.