FYI, we opened an SR for this with MS about a few weeks ago and it is currently escalated to the DEV team. The consensus thus far is that there does appear to be a defect calculating the PLE value in 2012; I will update when more information from MS is available in the event anyone else is experiencing this.

Some additional info:

SQL Server 2012 Core Edition

4 Socket 8 Core Xeon w/ HT enabled, 128GB, 112GB max memory

We have been collecting the ring buffer outputs for RING_BUFFER_RESOURCE_MONITOR and they do not show any new entries around the time when PLE dropped. Moreover during this timeframe, Page Reads/sec value do not fluctuate much indicating that we did not have to read a bunch of new pages into memory. The query with max reads around this time frame was 32K