Axiom 8GB DDR2-667 ECC RDIMM Kit (2 x 4GB) for Sun # X4063A, X4063A-Z - 8GB (2 x 4GB) - 667MHz DDR2-667/PC2-5300 - ECC - DDR2 SDRAM - 240-pin DIMM

667 MHz of memory speed makes your computer great at multitasking RDIMM 8 GB of memory to heighten your computers performance DDR2 SDRAM interface multiplexes 2-bit data from memory cell and I/O buses to minimize processor idle time and enhance your computers performance