We tried to confirm whether the availability of passive listening “Hey Cortana” feature of Lumia Denim update is dependent on the processor of Lumia devices. Sadly, it seems to be the case for now.
As confirmed by Sandeep Paruchuri from Microsoft, only devices with Snapdragon 800 processors will get the feature for now, but he hints that things may change in future, by saying “we understand the broader desire though”.
You can read more about Lumia Denim at our dedicated page and watch “Hey Cortana” in action by clicking here.