General

Brand	Samsung
Model	SM841
Capacity	128GB
Usage Class	Client

Interface

Host Interface	SATA
Total Interface Bandwidth	6 Gb/s

Physical Dimension

Form Factor	2.5

Flash & Endurance

NAND Flash	MLC
Drive Writes Per Day	0.5
Total Bytes Written	75 TBW

Performance

Sequential Read	530 MB/s
Sequential Write	130 MB/s
Random Read IOPS	85000
Random Write IOPS	35000
Average Latency	50 μs

Reliability

Mean Time Between Failures	1.5 Million Hours
Uncorrectable Bit Error Rate	1.0×10⁻¹⁷
Power Loss Protection	No

Part Number

MPN	MZ-7PC128

Engineer's Note

Compared with the earlier MZ-7PC128, the SM841 MZ-7PD1280/0H7 represents a clear generational upgrade in enterprise-readiness, combining 75 TBW / 0.5 DWPD MLC endurance with 85,000/35,000 IOPS to better sustain mixed read-write boot, cache, and light virtualization workloads. Its 530 MB/s read performance pushes the SATA interface close to saturation, while the stronger write consistency and enterprise endurance profile make it a more dependable 128GB drop-in choice than the predecessor for always-on server deployments.

Endurance & Reliability

With an endurance rating of 75 TBW and 0.5 DWPD, this SSD is well suited for OS boot, application, and other light-to-moderate write workloads typical of a system drive. In practical terms, at around 20 GB of host writes per day, 75 TBW translates to roughly 10 years of use, giving procurement confidence for stable, non-write-intensive deployments. Its UBER rating of 1.0E-15 means the drive is designed for a very low unrecoverable read error rate, supporting dependable data integrity in normal enterprise operation. This model does not include power-loss protection, so while it is appropriate for systems with stable power or upstream UPS protection, it is best positioned for boot or read-centric roles rather than write-critical caching or journaling applications.

Technical Specs & Insights

1. The SATA interface ensures broad compatibility with existing enterprise servers and storage arrays, enabling straightforward drop-in upgrades without platform changes.
2. With 530 MB/s sequential read performance, the drive accelerates large-file access, helping speed up backups, media delivery, and database snapshot reads.
3. Its 85,000 K IOPS random read capability supports highly concurrent transactional and virtualized workloads, reducing bottlenecks when many small data requests hit the storage layer at once.
4. Rated at 0.5 DWPD and built on MLC NAND, the SSD offers a balanced endurance profile for read-centric enterprise deployments that still require stronger write resilience than typical client-class flash.
5. A typical latency of 50 µs helps applications respond more consistently, which is especially valuable for OLTP, VDI, and other latency-sensitive business services.

Capacity Sweet

Lower-capacity reference: 64GB Higher-capacity reference: 256GB In this series, the 128GB model sits at the practical sweet spot. Compared with the 64GB version, it gives much better headroom for OS images, logs, swap, metadata, and moderate application growth, reducing early capacity pressure. Compared with the 256GB option, it preserves essentially the same enterprise-class sequential throughput and random IOPS profile while keeping acquisition cost and stranded capacity under tighter control. This makes 128GB especially suitable for small-to-mid virtualization clusters, such as hosting boot volumes for about 40 to 60 lightweight virtual machines or compact edge infrastructure nodes.

FAQ