Did you do a clean driver install? It should be a significant difference. And no its not bottlenecking.
Er.. No. A gtx1060 has performance level about the same as a GTX titan Black...
Sorry for the late reply. Was on reservist.
Will try a full clean/fresh install tonight.
Just to set the context, my main point of comparison is playing overwatch 1080p at 144hz. I play on the lowest setting on the gtx670 so as to consistently get > 144fps. I thought I could raise some of the settings after switching to gtx1060. However, if I were to raise the textures and stuff to medium, I would sometimes drop below 144fps and I didn't like it.
Hence, I didn't really feel much of a difference on the upgrade.
Also, when talking about bottlenecking, its in the context of the above + trying to stream with shadowplay. It seems like the CPU is consistently reaching 90% to 100% (GPU remains around 60%) and my frame rates drop noticeably. My impression is that shadowplay uses GPU (NVenc) and should not affect CPU?
EDIT: Just reviewed my footages. I realised that I also reach around 90% CPU without shadowplay streaming... However, I can notice lag/frame drops with streaming compared to not streaming.
EDIT2: Here a non-streaming version of my gameplay with the CPU and GPU % on the top left corner. Looks like CPU bottlenecking to me?