Wow, we knew that the latest iMac family had loads of overlooked enhancement, and this is no exception, the Imac sports souped up WiFi capable of hitting 450 Mbps speeds over wireless networks. Hardmac spotted a reference to this capability in the iMac’s system information. Apple first brought rhe 450Mbps WiFi features in the 2011 MacBook Pro family, but they haven’t been actively advertising it.
Apple changed their Airport card and also installed 3 antennas (instead of 2 before), something indispensable to be able simultaneously to use 3 channels of 150 Mbits/s.
According to 9to5mac.com to take advantage of the 450Mbps data transfer you need a compatible base station (either the current-generation Airport Extreme or Time Capsule). Make sure to connect to the base station using the 802.11n mode on the five gigahertz band GHz, with the simultaneous dual-band mode turned on.