The 21-inch model with a 2.7GHz quad-core Intel Core i5 processor uses very capable Iris Pro graphics. The high-end 21.5-inch model and both 27-inch iMacs feature quad-core Intel Core i5 processors up to 3.4GHz, and Nvidia GeForce 700 series graphics with twice the video memory and up to 40% faster performance than before. The new iMacs feature 802.11ac Wi-Fi, up to three times faster than 802.11n. In June 2014, an £899 entry-level model was added, offering a 1.4GHz dual-core processor and a 500GB hard drive. It’s tempting, but comparatively poor value.