The Intel S4500 Entry SATA solid-state drives (SSDs) for Lenovo servers use Intel 3D NAND TLC Flash Memory technology with a 6Gbps SATA interface to provide an affordable solution with industry leading performance. This product guide provides essential presales information to understand the S4500 SSD offerings, their key features and specifications, components and options, and configuration guidelines. This guide is intended for technical specialists, sales specialists, sales engineers, IT architects, and other IT professionals who want to learn more about S4500 SSDs and consider their use in IT solutions. The Intel S4500 Entry SATA solid-state drives (SSDs) for Lenovo servers use Intel 3D NAND TLC Flash Memory technology with a 6Gbps SATA interface to provide an affordable solution with industry leading performance. Compared with the Intel S3520 series, these new drives offer improved performance and lower latency. The S4500 SSDs are optimized for read-intensive applications such as boot, web servers, lower data rate operational databases and analytics. 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. Enterprise Entry SSDs typically have a better cost per read IOPS ratio but lower endurance and performance compared to Enterprise Performance SSDs. SSD write endurance is typically measured by the number of program/erase cycles that the drive can incur over its lifetime, which is listed as total bytes written (TBW) in the device specification. The TBW value that is assigned to a solid-state device is the total bytes of written data that a drive can be guaranteed to complete. Reaching this limit does not cause the drive to immediately fail; the TBW simply denotes the maximum number of writes that can be guaranteed. A solid-state device does not fail upon reaching the specified TBW. However, at some point after surpassing the TBW value (and based on manufacturing variance margins), the drive reaches the end-of-life point, at which time the drive goes into read-only mode. Because of such behavior, careful planning must be done to use SSDs in the application environments to ensure that the TBW of the drive is not exceeded before the required life expectancy. For example, the S4500 Entry 960 GB drive has an endurance of 1,860 TB of total bytes written (TBW). This means that for full operation over five years, write workload must be limited to no more than 1,019 GB of writes per day, which is equivalent to 1.1 full drive writes per day (DWPD). For the device to last three years, the drive write workload must be limited to no more than 1,699 GB of writes per day, which is equivalent to 1.8 full drive writes per day.