HTC One M9 using Snapdragon 810 v2.1, adds more confusion to overheating saga
Jeff Gordon, HTC's senior global online communications manager, confirmed in a tweet that the One M9 is using the improved version of Qualcomm Snapdragon 810 chipset known as v2.1. He also understands from Qualcomm that "virtually all OEMs who've announced devices with Snapdragon 810 are currently using v2.1".