Abstract
The PM1643a Entry SAS 12Gb solid-state drives (SSDs) from Lenovo provide high-performance, reliable storage solutions for high-capacity enterprise applications. Designed for dense storage and with a 12 Gb SAS interface, these drives feature all the capacity and performance that is needed to replace large numbers of 15K rpm and 10K rpm spinning disks, and consolidate storage into tightly packed server configurations.

This product guide provides essential presales information to understand the PM1643a Entry SAS 12Gb SSD offerings and their key features, specifications, and compatibility. This guide is intended for technical specialists, sales specialists, sales engineers, IT architects, and other IT professionals who want to learn more about the SSDs and consider their use in IT solutions.

Introduction
The ThinkSystem PM1643a Entry SAS 12Gb solid-state drives (SSDs) are next-generation SSDs suitable for a wide range of applications. The PM1643a SAS SSDs are designed for dense storage and with a 12 Gb SAS interface, these drives feature all the capacity and performance that is needed to replace large numbers of 15K rpm and 10K rpm spinning disks, and consolidate storage into tightly packed server configurations.

The PM1643a SSDs are the follow-on to the PM1643 SSDs and offer improved random write performance.

Did you know?
Unlike SATA drives, the 12 Gb/s SAS interface on PM1643a drives supports full duplex data transfer for higher performance, as well as enterprise-level error recovery for better availability.

Rigorous testing of PM1643a Entry SATA SSDs by Lenovo through the ServerProven program assures a high degree of storage subsystem compatibility and reliability. Providing additional peace of mind, these drives are covered under Lenovo warranty.

SSDs have a huge but finite number of program/erase (P/E) cycles, which affect how long they can perform write operations and thus their life expectancy. Entry SSDs typically have a better cost per read IOPS ratio but lower endurance and performance compared to Mainstream or Performance SSDs.

SSD write endurance is typically measured by the number of program/erase (P/E) cycles that the drive incurs over its lifetime, listed as the total bytes of written data (TBW) in the device specification. The TBW value assigned to a solid-state device is the total bytes of written data (based on the number of P/E cycles) that a drive can be guaranteed to complete (% of remaining P/E cycles = % of remaining TBW).

Reaching this limit does not cause the drive to immediately fail. It simply denotes the maximum number of writes that can be guaranteed. A solid-state device will not fail upon reaching the specified TBW. At some point based on manufacturing variance margin, after surpassing the TBW value, the drive will reach the end-of-life point, at which the drive will go into a read-only mode.

Specification

Product
Product id	712295
Brand	Lenovo
Partnr	4XB7A38176
EAN/UPC code	889488506095
Certificates
Certification	UL, TUV, FCC, IC, CB, C-Tick Mark, BSMI (Taiwan), KCC (Korea EMI), VCCI
Features
SSD form factor	2.5"
SSD capacity	1920 GB
Interface	SAS
Memory type	V-NAND TLC
Component for	Disk array
Data transfer rate	12 Gbit/s
Read speed	1000 MB/s
Write speed	1000 MB/s
Random read (4KB)	230000 IOPS
Random write (4KB)	60000 IOPS
Read latency	240 µs
Write latency	220 µs
S. M. A. R. T. support	Y
Hot-swap	Y
Uncorrectable Bit Error Rate (UBER)	< 1 per 10^17 bits read
Mean time between failures (MTBF)	2000000 uur
Power
Power consumption (read)	9 W
Power consumption (write)	12 W
Operational conditions
Operating relative humidity (H-H)	5 - 95 procent
Operating temperature (T-T)	0 - 70 °C
Storage temperature (T-T)	-40 - 85 °C
Operating vibration	20 G
Operating shock	1500 G
Maximum operating altitude	4572 m
Technical details
Sustainability certificates	CE, RoHS
Weight & dimensions
Width	70 mm
Depth	100 mm
Height	15 mm
Weight	158 g
Packaging data
Package width	133 mm
Package depth	174 mm
Package height	63 mm