4GB 240p PC2-5300 CL5 36c 256x4 DDR2-667 2Rx4 1.8V ECC FBDIMM. Compatible with Servers. 2RX4 "THIS MEMORY IS NOT FOR DESKTOPS" SERVER MEMORY, Not for home PC. Additional Details ------------------------------ Is autographed: false Is memorabilia: false Package quantity: 1