Here is a good page from about September of 2013 that shows around what each video/CPU can do in the game. The site is in Russian but Google translate should make parts of it readable.
http://gamegpu.ru/action-/-fps-/-tps/arma-iii-test-gpu.html (the charts start about 1/2 down)
This info is a year old and the game from what I can tell runs a better now than it did at release. As long as you have the CPU power add about 10fps to the numbers in the chart. (My work system with a gtx460 is very playable (about 40-45fps with the benchmark below) where on the chart its slow)
I have played it some on an Athlon x6 1045t @2.8ghz and a GTX260 @1920x1080 and that is about as low as I would want to go, as it was both CPU and video limited at different times.
http://www.armaholic...ge.php?id=19801 <-- here is a link for a benchmark scenario follow the instructions on where to put it and run it in game it will return a result after it is done.
Edited by CrashMaster, 11 November 2014 - 12:36 PM.