The Samsung 990 PRO NVMe SSD and Synology DS923+ serve fundamentally different purposes: one is a high-speed internal drive, the other a network storage appliance. The 990 PRO wins on raw sequential performance (7450/6900 MB/s per Samsung) while the DS923+ provides Ryzen R1600 CPU, expandable RAM, and DSM features (per Synology specs). They are not direct substitutes.