PM1645a SSD Buyer's Guide: Specs, Pricing, and Upgrade Paths

The Samsung PM1645a remains a cornerstone of the 12Gb/s SAS enterprise market, though it is increasingly viewed as a legacy solution compared to the newer 24Gb/s PM1653 and the industry-wide pivot toward NVMe Samsung Compuram.

Product Insights & Comparison

The PM1645a (SAS-3) provides reliable 12Gb/s throughput, widely utilized in OEM servers from HPE, Dell, and Lenovo. However, the PM1653 (SAS-4) doubles performance across nearly all metrics, reaching up to 4,300 MB/s sequential read and 800k IOPS random read Samsung Semiwiki Samsung.

Metric	PM1645a (12G SAS)	PM1653 (24G SAS)
Interface Speed	12 Gb/s	24 Gb/s
Sequential Read	~2,100 MB/s	Up to 4,300 MB/s
Random Read	~400,000 IOPS	Up to 800,000 IOPS
NAND Tech	V-NAND TLC	6th Gen V-NAND (128-layer)

Market Trends (2026)

* The SAS Sunset: Samsung has signaled that no new SAS models are planned beyond 2026, marking a final shift toward NVMe for all high-performance deployments Youtube Samsung.

* AI-Driven Price Volatility: Driven by AI training and data center expansion, enterprise SSD pricing has seen surges of up to 80% in early 2026 Alibaba.

* Capacity Growth: High-capacity segments (>2TB) are growing fastest, with roadmaps for 128TB and 256TB drives targeted to satisfy AI inference requirements by late 2026 Unibetter-Ic Persistencemarketresearch.

Sourcing & Pricing

* PM1645a (800GB - 3.2TB): Retail prices range from $250 to over $2,000 for brand-new OEM variants Google Google. Wholesale B2B pricing for 1.6TB models is currently around $450/unit Alibaba.

* PM1653 (High Capacity): Flagship 30.72TB models are currently sourcing at approximately $7,100 on B2B platforms Alibaba.