>> ARM Cortex-A15: 3.5
>> ARM Cortex-A57: 4.1...4.8 (depending on implementation)

> So if the A57 is slower, the 32 bit A15 will still lead even when the A57 is introduced.
> Curious.

The Cortex-A15 is specified for a maximum clock rate of 2.5 GHz (while current chips using that core don't exceed 1.9 GHz). Even if we take the slowest figure of 4.1 DMIPS for the Cortex-A57, it will take a 2.1 GHz Cortex-A57 to beat a 2.5 GHz Cortex-A15. Do you think the Cortex-A57 will be introduced with a clock rate below 2.1 GHz?