I just ran the most demanding showcase with this PC (Actually RAM has been upgraded to 16GB 1600). The Helicopter one.

I used HWiNFO64 to monitor my GPU and CPU clocks. During the entire showcase my GPU load never went above 40%, and my CPU load was at around 40-60% load the entire time. Max FPS during gameplay was 25. Average was at 19 FPS

This to me is unacceptable with the type of rig that I have. And it is clear that Arma 3 can not utilize my hardware. This should be addressed ASAP.

Settings where custom with rendering at Very High settings and AA turned off and view range was at 2000.

I have the same exact issue.

GPU: Nvidia GTX 670 (OC to 1300 MHZ)
CPU: Phenom II x4 Black Edition 965
RAM: 16GB DDR3 1600.

Both in single player and multiplayer. Did the helicopter showcase, got an avrage of 19 FPS. Peaked at 25 but keept arround 15 for most of the game. GPU never came above 40% load, CPU never came above 55%-60% load. I know the game is in alpha, but this has to be fixed ASAP since it makes the game totaly unplayable for me. Running a FPS game released in 2013 with the same FPS as Super Mario had on the NES is kinda ridiculous in my opinion.