Stefan Mileschin

​Today in London as part of ARM's TechDay 2015 event we had the pleasure to get a better insight into ARM's new Cortex-A72 CPU. ARM had announced the A72 in the beginning of February - leaving a lot of questions to be asked and sense of mystery in the air. The A72 is a direct successor to the A57 - taking the predecessor as a baseline in order to iterate and improve it.

On the naming side of the equation, moving from 'A57' to 'A72' rather than 'A59' or similar, ARM explains that it is purely a marketing decision as they wanted to give better differentiation between its higher-performance cores from the mid-tier and low-power cores. There seemed to be some confusion between the more power efficienct A53 and the more powerful A57, whereby vendors would assume they are similar, and thus moving its new big core into the A7x series.

We saw some absolute targeted performance numbers back during the February release, which promised some very interesting numbers over what the A57 could achieve. The problem was that it was not clear how much from performance and power efficiency came from the architectural changes and how much came from the the process on which these targeted performance data points are estimated from. It's clear that on the high-end ARM is promoting the A72 on the new FinFET processes from Samsung/GlobalFoundries and TSMC, which are referred to as 14nm and 16nm in the slides. Generally, due to the design and the node, the A72 will be able to achieve higher clocks than the A57, and we seem to be aiming around 2.5GHz on the 14/16nm nodes when high-end smartphones are concerned. Higher clocks may be present in server applications, where the A72 is also aimed at.

http://www.anandtech.com/show/9184/a...ecture-details