Make sure to set up LOD’s for your enemies =)
With my old system i had a VR demo with 40+ zombies walking around and it ran at 90fps. Adding LOD’s made a lot of difference in terms of performance. (I had a GTX 780, i7-2600k, 8GB ram)
But yeah, start with running Stat unit to see what’s really taking up a lot. Or tune in to the stream I guess =P