Display 21.5-inch (diagonal) LED-backlit display with IPS technology; 1920-by-1080 resolution with support for millions of colors Processor 2.7GHz 2.7GHz quad-core Intel Core i5 processor (Turbo Boost up to 3.2GHz) with 4MB L3 cache 2.9GHz 2.9GHz quad-core Intel Core i5 processor (Turbo Boost up to 3.6GHz) with 6MB L3 cache Configurable to 3.1GHz quad-core Intel Core i7 (Turbo Boost up to 3.9GHz). Memory 8GB (two 4GB) of 1600MHz DDR3 memory Configurable to 16GB. Storage1 1TB (5400-rpm) hard drive Configurable to 1TB Fusion Drive or 256GB or 512GB of flash storage. Graphics 2.7GHz Intel Iris Pro graphics 2.9GHz NVIDIA GeForce GT 750M graphics processor with 1GB of GDDR5 memory Video Support and Camera FaceTime HD camera Simultaneously supports full native resolution on the built-in display and up to a 30-inch display (2560 by 1600 pixels) on an external display Support for extended desktop and video mirroring modes Support for Target Display Mode via the Thunderbolt port using a Thunderbolt to Thunderbolt cable (sold separately) Audio Stereo speakers Dual microphones Headphone port Headphone/optical digital audio output (minijack) Support for Apple iPhone headset with microphone Connections and Expansion SDXC card slot Four USB 3 ports (compatible with USB 2) Two Thunderbolt ports Mini DisplayPort output with support for DVI, VGA, and dual-link DVI (adapters sold separately) 10/100/1000BASE-T Gigabit Ethernet (RJ-45 connector) Kensington lock slot