Trundra vegetation. I eliminated Speed Trees. I have never seen trees that look like many of them. So, went to compatibility mode and replaced everything with vegetation from Trunda. Stuttering is reduced. While you loose some FPS in compatibility mode you gain some from not using Speed Trees. 50fps seems good for:
2ghz dualcore, 2gb memory, nVidia 240 512mb video card

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2ghz dualcore, 2gb memory, nVidia 240 512mb video card

Uploaded with ImageShack.us