What Catalyst?
And what card?
Running 10.9 (almost as fast as 11.1a, but that version gives me an issue) on a 5970 with these settings:
AA 4X
CF EdgeDetect
(this combination is actually as good as AA16x, but far smoother to run)
AF 16X
A.I. Standard (2 gpu)
MM Detail HQ
Vert. Sync ON
AA Mode SSAA
Triple Buffering OFF
Settings in Silent Hunter IV:
[Current]
DepthBufferEffects=1
Filters=1
Glare=1
UnderwaterDispMap=1
LightShafts=1
3DShipWakes=1
DetailedWaveRipples=1
UnitNormalMaps=1
ShipCausticsEffects=1
Ship3DDamage=2
CharacterDetail=1
ParticlesDetail=9
TerrainObjectsDensity=7
TerrainObjectsLODSize=7
GammaCorrection=50
VolumetricFog=1
Some reduced samples...