Google Nexus phones are known for its high end specifications and stock Android OS. The upcoming Nexus 5 (2015) AnTuTu benchmark scores have been leaked that shows a jaw dropping score of 85,530. The closes competitor that remotely nears the Nexus 5 (2015) are the Galaxy S6 / S6 Edge models.
High scores do suggest that the cell phone could very well be powered by a Qualcomm Snapdragon 820 SoC. The handset is also rumored to have a different design from LG G4. The device is also said to come in LG and Huawei make.
We will have to wait and see to know the full phone specifications however it is almost confirmed that, the upcoming nexus phone will be a beast in terms of processing power.