I had Windows Defender active in backgound, not scanning, and arma3.exe and steam were in exception list. No other security applications running. RAM was tested and is OK. Drives in good shape. Steam and Arma3 launcher alng with arma3.exe were not runnning with elevated permissions. I did have steam FPS counter and overlay running but not active ( which I never used before and may be the cause ).
dxdiag here: http://pastebin.com/UrGsXLFw
event log : http://pastebin.com/LLbCQias
rpt and dumps in attachment