I'll mark the relevant settings from my config.ini setting in main install folder, keep in mind I did not set this to the max for IL-2, still deactivated some options like dynamical lights or max LandGeom=3, since those caused some minor issues with my driver.
[Render_OpenGL]
TexQual=3
TexMipFilter=3
TexCompress=0
TexFlags.UseDither=0
TexFlags.UseAlpha=0
TexFlags.UseIndex=0
TexFlags.PolygonStipple=0
TexFlags.UseClampedSprites=0
TexFlags.DrawLandByTriangles=0
TexFlags.UseVertexArrays=0
TexFlags.DisableAPIExtensions=0
TexFlags.ARBMultitextureExt=1
TexFlags.TexEnvCombineExt=1
TexFlags.SecondaryColorExt=1
TexFlags.VertexArrayExt=1
TexFlags.ClipHintExt=1
TexFlags.UsePaletteExt=0
TexFlags.TexAnisotropicExt=1
TexFlags.TexCompressARBExt=0
TexFlags.TexEnvCombine4NV=0 1 for NVidia!
TexFlags.TexEnvCombineDot3=1
TexFlags.DepthClampNV=0 1 for NVidia
TexFlags.SeparateSpecular=1
TexFlags.TextureShaderNV=0 1 for NVidia
HardwareShaders=1Shadows=2
Specular=2
SpecularLight=2
DiffuseLight=2
DynamicalLights=0
MeshDetail=2
VisibilityDistance=3
Sky=2
Forest=3
LandShading=3
LandDetails=2
LandGeom=2
TexLarge=1
TexLandQual=3
TexLandLarge=1
VideoSetupId=17
Water=2 ...4 for NVidia and max!Effects=2
ForceShaders1x=1
PolygonOffsetFactor=-0.15
PolygonOffsetUnits=-3.0
Good Luck, your NVidia should give you best water looks!