HP 16GB 240-Pin DDR3 SDRAM ECC Registered DDR3 1333 (PC3 10600) Server Memory Model 647901-S21 Voltage: 1.35V Compatible System: Designed For: HPE ProLiant SL250s Gen8 Base 2U Left Tray Server, SL250s Gen8 Base 2U Right Tray Server Cas Latency: 9 Rank: 2Rx4