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 Intuitive touchscreen technology lets you control your PC right from the screen. And the vibrant 1980 x 1200 resolution delivers 2 million pixels for crystal-clear visuals 1920 x 1080 Y Full HD Intel® Pentium® Intel Pentium G DisplayPort 1 Hard Drive HDD HP ProOne 400 G1, 21.5", Full HD, Intel Pentium G, 4 GB, 500 GB, Windows 8.1 Pro HP ProOne 400 G1. Product type: All-in-One PC. Display diagonal: 21.5", HD type: Full HD, Display resolution: 1920 x 1080 pixels, Touchscreen. Processor family: Intel Pentium G, Processor frequency: 2.7 GHz. Internal memory: 4 GB, Internal memory type: DDR3-SDRAM. Total storage capacity: 500 GB, Storage media: HDD. Built-in camera. Optical drive type: DVD Super Multi. Operating system installed: Windows 8.1 Pro. Product color: Black, Silver