Why the texture of land is blink?

[inferno7312]

I built a new computer with 8800GT
but when I run IL2, I found the texture of forest blink! particularly, the texture of forest where is far from the focus.
I downloaded the newest dll file and newest nvidia card driver. it still blink.... I attached a screenshoot here.
Anyone know how to solve it?

video card setting.

anisotropic :Application-controller
antialiasing-gamma correction : off
antialiazing-mode : override any application setting
antializsing-setting : 4x
antialiasing-transparency : off
conformant texture clamp : use openGL specification
Force mipmaps : trilinear
Maximum pre-rendered frames: 0
multi-display: singel
Textur filtering -anisotropic sample op... : off
texture filtering- negative LOD bias: allow
texture filtering-triliner optimization: off
Threaded optimization: auto
triple buffer: on
texture filtering- anisotropic mip filiter optimization: off
vertical sync: force on