Crucial 8GB Kit (4GBx2) DDR2-667MHz (PC2-5300) CL5 ECC RDIMM DR 240pin Server Memory CT2KIT51272AB667/ CT2CP51272AB667 Increases system performance Easy to install Premium quality memory from a trusted brand 100% Tested Limited Lifetime Warranty 240-pin DIMMs are used to provide DDR2 SDRAM memory for desktop computers To use DDR2 memory, your system motherboard must have 240-pin DIMM slots and a DDR2-enabled chipset Each 240-pin DIMM provides a 72-bit for ECC or registered or fully buffered modules