Crucial BX500 120GB

The Crucial BX500 120GB utilizes a streamlined, DRAM-less architecture, typically pairing a Silicon Motion controller (commonly the SM2258XT or SM2259XT) with Micron’s proprietary 3D NAND flash. As a legacy SATA III implementation, the drive relies entirely on pseudo-SLC caching algorithms to maintain sequential throughput, compensating for the absence of a volatile memory buffer. The 120GB capacity point generally necessitates the use of TLC NAND due to die-density limitations of QLC in lower-capacity volumes. This model is noted for its plastic enclosure, which acts as a thermal insulator rather than a heatsink and can lead to higher controller temperatures during sustained transfers. The drive has seen silent revisions where internal components change without a model-number update, and sustained write performance drops significantly once the SLC cache is saturated, a characteristic behavior of the SM2258XT architecture during garbage collection.

Key Specifications

• Interface: SATA III (6Gb/s)
• Sequential Read/Write: 540 MB/s / 500 MB/s
• Controller: Silicon Motion SM2258XT or SM2259XT (DRAM-less)
• NAND Type: Micron 3D NAND (Variable)
• Form Factor: 2.5-inch (7mm z-height)
• Features: Dynamic SLC Caching, Multistep Data Integrity Algorithm, Plastic Chassis

Hardware Alternatives

• Kingston A400: A direct architectural competitor often utilizing the Phison S11 controller, occupying the same hardware tier and omitting DRAM caching for simpler PCB designs.
• ADATA SU650: Frequently shares the same Silicon Motion SM2258XT controller as the BX500, making them functional siblings depending on NAND batches.
• WD Green / SanDisk SSD Plus: Proprietary alternatives that target similar I/O levels but use Western Digital’s in-house controller and NAND integration with a different firmware approach to DRAM-less designs.