The iMac Core i7 4.0 27-Inch Aluminum (Retina 5K, Late 2015/Skylake) technically is a configure-to-order configuration of either the iMac Core i5 3.2 27-Inch Aluminum (Retina 5K, Late 2015/Skylake) or iMac Core i5 3.3 27-Inch Aluminum (Retina 5K, Late 2015/Skylake), but also is documented as a separate model for reader convenience. Other than processor (and the corresponding level 3 cache), this custom model is identical to its stock counterpart. The iMac Core i7 4.0 27-Inch Aluminum (Retina 5K, Late 2015/Skylake) features a 14-nm Skylake Quad Core 4.0 GHz Intel Core i7 processor (6700K) with four independent processor cores on a single chip, an 8 MB shared level 3 cache, 8 GB of 1867 MHz LPDDR3 SDRAM (PC3-14900) installed in pairs (two 4 GB modules), a 1 TB or 2 TB Fusion Drive, and an AMD Radeon R9 M390 or AMD Radeon R9 M395 graphics processor with 2 GB of dedicated GDDR5 memory. It also has a built-in FaceTime HD webcam and stereo speakers. This model has a 27 5120x2880 LED-backlit 16:9 widescreen IPS DCI-P3 Retina 5K display. The rear of the case is aluminum and is thicker in the middle and tapers to a razor thin 5 mm at the edges. Connectivity includes four USB 3.0 ports, dual Thunderbolt 2 ports, Gigabit Ethernet, 802.11ac Wi-Fi (802.11a/b/g/n compatible), and Bluetooth 4.0. Compared to its predecessor, this model essentially has the same external enclosure, but it has a higher quality DCI-P3 Retina 5K display with a wider color gamut as well as a more advanced architecture and graphics architecture.