This Dell® A6993740 compatible 2x4GB DDR2-667MHz DDR2-667MHz dual rank Fully Buffered ECC 1.8V 240-pin CL5 factory original FBDIMM is 100% guaranteed to be compatible with your system and to work right the first time. Adding additional memory is the best way to increase the performance of your system. All our memory is built to strict JEDEC standards to meet or exceed the Tier 1 OEM's factory requirements. Our products are also guaranteed by the Magnuson-Moss Warranty Act to not affect or void OEM warranties.