Komputerbay 8GB (2X 4GB) DDR2 PC2-6400F 800MHz ECC Fully Buffered FB-DIMM (240 PIN) 8 GB w/Heatspreaders for Apple Computers ECC Fully Buffered (an FBDIMM will not fit into a standard DDR2 socket, and a DDR2 module will not fit into an FBDIMM socket) Capacity: 8GB For Apple Mac Pro (8-core) Desktop Speed: PC2-6400F 800MHz 240-Pin DIMM Lifetime Warranty