ADATA Ultimate SU630 960GB

The ADATA Ultimate SU630 960GB uses the Maxio MAS0902A controller in a DRAM-less architecture and is one of the early adopters of 3D QLC NAND. To compensate for the lack of DRAM and higher latency of QLC media, the drive relies on a dynamic pseudo-SLC (pSLC) caching algorithm to handle incoming data bursts. Technical analysis shows a pronounced write cliff: while the drive hits advertised speeds within the pSLC cache, sustained writes that exceed the cache capacity drop to native QLC speeds (which can fall below 50 MB/s). As the drive fills, available pSLC space shrinks, worsening sustained write performance, so the architecture is best categorized as a read-intensive boot or secondary storage solution rather than a workspace for heavy write cycles.

Key Specifications

• Interface: SATA III (6Gb/s)
• Controller: Maxio MAS0902A
• NAND Flash: 3D QLC (Quad-Level Cell)
• DRAM Cache: None (DRAM-less)
• Sequential Read: 520 MB/s
• Sequential Write: 450 MB/s
• Error Correction: LDPC (Low-Density Parity-Check) ECC
• Endurance Rating: Variable by batch, generally lower TBW compared to TLC equivalents.

Hardware Alternatives

• Crucial BX500 960GB: A direct architectural competitor in the DRAM-less SATA sector; later revisions frequently utilize QLC NAND similar to the SU630, resulting in a nearly identical performance profile regarding sustained writes and random I/O latency.
• Samsung 870 QVO: Shares QLC NAND technology with the SU630 but pairs it with a proprietary controller and dedicated LPDDR4 DRAM, offering higher sustained performance and more consistent random read/write behavior.
• ADATA Ultimate SU650: An internal hardware relative within ADATA’s lineup that typically uses 3D TLC NAND, offering superior endurance and native write speeds compared to the SU630's QLC, though both drives often share similar DRAM-less controller logic.