At least 2 GB

13.3 MacBook Pro Notebook Computer with Retina Display, 2.5GHz Intel Core i5 Dual-Core, 8GB of 1600MHz DDR3L RAM, 768GB Flash Storage, Integrated Intel HD Graphics 4000, 13.3 LED-Backlit IPS Retina Display, 2560 x 1600 Native Resolution, 802.11a/b/g/n Wi-Fi, Bluetooth 4.0, Thunderbolt, USB 3.0, HDMI, 720p FaceTime HD Camera, Dual Mics, Mac OS X 10.8 Mountain Lion (64-bit)

13.3 (1440x900) High-Resolution LED-Backlit Glossy Widescreen Display/ Turbo Boost Up To 3.2GHz/ 256GB Flash Storage/ 3MB Shared L3 Cache/ 8GB 1600MHz DDR3L Memory/ Intel HD Graphics 4000/ 720p FaceTime HD Camera/ Dual Display And Video Mirroring Support/ USB 3/ Thunderbolt/ MagSafe 2 Power Port/ SD Card Slot/ 802.11n Wi-Fi Networking/ Bluetooth 4.0/ Full-Size Backlit Keyboard/ OS X Mountain Lion/ Aluminum Finish

Introducing the 15.4-inch MacBook Pro. The state-of-the-art quad-core Intel i7 processor delivers up to 2x faster performance (over the previous generation of MacBook Pro). New Thunderbolt technology lets you connect high-performance peripherals and high-resolution displays to a single port, and transfer files at lightning speeds. And with the built-in FaceTime HD camera, you can make astonishingly crisp HD video calls. With the revolutionary Thunderbolt technology, you'll be able to achieve bi-directional channels with transfer speeds to peripherals like external hard drives and servers up to an amazing 10 Gbps--while also connecting to a DisplayPort- compatible high-resolution display. As with previous models, the MacBook Pro features a precision unibody enclosure crafted from a... Less