SherlockinHD

So I'm playing ArmA 3, Ultra (NoAA) and 40FPS, or something like that. Great. I play DayZ and I look at the ocean, 60FPS. Pretty good, then I turn around and look to the land. 20FPS. Not so good. Even in buildings i have great FPS when i look to the South (?) (ocean direction), but when i look at a wall that is to the land-side (North?) I get lag. Everything is on Low, res at 1920x1080. i5-3450 ATi HD7770 Ghz Edition 8GB RAM 2TB 7200RPM.