Arma 3 A Hardcore Survival Scenario

You are stranded on an small island for no particular reason. Helos are out to kill you. Stay inside the marked area,else u lose. Survive for 5 minutes to win. Shoot down incoming helicopters to increase your chance of winning. My PC Specs CPU AMD FX-6300 3.5 Ghz 6 Core CPU GPU XFX 7870 Radeon Double D 2gb PSU XFX Pro 750Watt MB BioStar A960G+ 8GB DD3 Ram 1TB Sata Hard Drive Thermaltake Case OS Windows 7 Home Premium (64bit) Acer 23" Widescreen Flat Panel LED HD Monitor