This HP 647899-B21 compatible 8GB DDR3-1600MHz Single Rank Registered ECC 1.5V 240-pin CL11 factory original RDIMM is 100% guaranteed to be compatible with your system and to work right the first time. Adding additional memory is the best way to increase the performance of your system. All our memory is built to strict JEDEC standards to meet or exceed the Tier 1 OEM's factory requirements. Our products are also guaranteed by federal law to not affect or void OEM warranties.

• DIMM 8 GB memory allows you to have more programs open at a time
• 240-pin-pin DDR3-1600/PC3-12800 operates at an effective bus speed with minimal power consumption and as a result, you get optimal computer performance with an improved memory heat dissipation
• No matter how heavy and numerous the applications that you are using, 1600 MHz memory speed with Registered signal will run them smoothly