ENERGY STAR® is the government-backed symbol for energy efficiency, providing simple, credible, and unbiased information that consumers and businesses rely on to make well-informed decisions. ENERGY STAR is the simple choice for energy efficiency, making it easy for consumers and businesses to purchase products that save them money and protect the environment. ENERGY STAR DELL OptiPlex XE SF, 3 GHz, Intel® Core™2 Duo, 4 GB, 500 GB, DVD±RW, Windows 7 Professional DELL OptiPlex XE SF. Processor frequency: 3 GHz, Processor family: Intel® Core™2 Duo, Processor model: E8400. Internal memory: 4 GB, Internal memory type: DDR3-SDRAM, Memory clock speed: 1333 MHz. Total storage capacity: 500 GB, Storage media: HDD, Optical drive type: DVD±RW. Operating system installed: Windows 7 Professional, Operating system architecture: 64-bit. Chassis type: SFF. Product type: PC. Weight: 6.48 kg. Product colour: Black