MacRumors has been offering up some interesting speculation that could explain why the expected Apple iMac refresh hasn’t been revealed yet. It seems possible that the OEM was waiting for Intel to release the Comet Lake-S desktop processors so that customers could enjoy a refreshed iMac with one of Team Blue’s latest and greatest 14nm CPUs. This includes the top-end Intel Core i9-10900K, which can reach clock rates of up to 5.3 GHz thanks to Thermal Velocity Boost (TVB).
The same source suggests the refreshed 21.5-inch iMac all-in-one could be fitted with Comet Lake chips such as the Intel Core i3-10100, Core i5-10500, or Core i7-10700. These would replace the current Coffee Lake options that the iMac series mostly offers (the entry-level model comes with a Kaby Lake i5-7360U processor). As for the 27-inch Apple iMac, it seems reasonable that these larger devices could cope with the Intel Core i5-10500, Core i5-10600, Core i5-10600K, and even the “world’s fastest gaming processor” that comes in the form of the 10-core i9-10900K.
With a 23-inch iMac all-in-one model apparently also in the works, this would make a purchase in 2020 much more attractive to those considering one of the multipurpose Apple desktop computers. As availability of the Comet-Lake S desktop parts has already begun, it might not be too long of a wait to see the refreshed iMac range make an appearance. However, it is believed the rumored 23-inch iMac won't be introduced until the second half of 2020. At the moment, the cheapest iMac costs from US$1,099 for the Kaby Lake-based 21.5-inch model, while the most expensive is the 27-inch all-in-one with a Core i9-9900KF that costs from US$2,229.