KOMPUTERBAY 16GB (8X2GB) Certified Memory for HP WORKSTATION XW8600 DDR2 667MHz PC2-5300 Fully Buffered ECC Fully Buffered (an FBDIMM will not fit into a standard DDR2 socket, and a standard DDR2 module will not fit into an FBDIMM socket) Capacity: 16GB Speed: PC2-5300F 667MHz CL 5 Thermal Heatspreaders for Cooling 240-Pin FBDIMM Fully Buffered Lifetime Warranty