405477-061 HP 8 GB REG PC2-5300 (2 x 4GB) dual rank

497767-B21 Overview

497767-B21 . Operates on 1.8 Volts within speeds between 533 and 800 MT/s (million transfers per second). This module has a total capacity of 4GB. The Bus Type is PC-6400. Its ECC (Error Correction Code) features prevent data corruption and system failure which is typically ideal for server machines. You can expect the data to transfer at a rate of 800 Mhz. 

728629-B21 Overview

Is finding reliable DRAM memory for your HP ProLiant Server series in your data center a major challenge? When you choose HP SmartMemory you get the same high quality, reliability, and confidence that come with your HP ProLiant Gen9 Server series. DRAM quality and reliability are more important now than ever. Industry trends such as server virtualization, cloud computing, the use of large database applications, and high-performance computing have all increased the need for higher capacity memory with greater reliability and uptime. HP SmartMemory is a unique technology introduced in HP ProLiant Gen8 Servers that unlocks certain features available only with HP Qualified Server memory in Gen9 servers also. HP SmartMemory enables ProLiant Gen9 systems to reliably identify and verify whether installed memory has passed the rigorous HP qualification and testing processes. And because the memory is authenticated, you can enable extended memory performance features through the system ROM.