KOMPUTERBAY 8 GB (4 GBx2) Apple Specific DDR2 PC2-5300 CL=5 Fully Buffered ECC DDR2-667 1.8V 128Meg x 72 Memory Kit 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: 8GB For Apple Mac Pro (8-core) Desktop Speed: PC2-5300F 667MHz CL 5 Thermal Heatspreaders for Cooling 240-Pin FBDIMM Fully Buffered Lifetime Warranty