This HP® FX621AA compatible 4GB DDR3-1333MHz dual rank registered ECC 1.5V 240-pin CL9 factory original RDIMM is 100% guaranteed to be compatible with your system and to work right the first time. All of our server memory is built to strict JEDEC standards at one of the tier 1 facilities (Samsung®, Micron®, or Hynix®). Our products are also guaranteed by federal law to not affect or void OEM warranties.
Up to 1333 MHz memory speed with Registered signal and CL9 to manage your routine softwares with pace and accuracy
DIMM 4 GB memory allows you to have more programs open at a time
DDR3 SDRAM interface multiplexes 2-bit data from memory cell and I/O buses to minimize processor idle time and enhance your computer's performance
