This Dell® A4188277 compatible Factory Original Tier 1 - 16GB DDR3-1066MHz 1.35V LRDIMM 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. 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.