Something

g_useProfile = 1
r_ShadersAsyncCompiling = 1
r_driver = "DX9"
net_wmi_check_interval = 0
r_height = 1024 (change to your res)
r_width = 1280 (change to your res)
r_UseEdgeAA = 1
r_sunshafts = 1
r_UsePom = 1
r_shownormals = 1
q_ShaderGlass = 2
sys_budget_videomem = 640 (your graphics mem)
r_TextureCompressor = 0
r_TexQuality = 3
r_PostProcessEffectsFilters = 1
sys_budget_sysmem = 2048 (your system mem)
r_VegetationSpritesTexRes = 128
r_UseNormals = 1
r_ShadersStaticBranching = 0
r_ShadersDynamicBranching = 1
r_VegetationSpritesAlphaBlend = 1
r_VSync = 0
r_fsaa = 1
r_FSAA_samples = 2
r_FSAA_quality = 1
r_WaterGodRays = 1
r_CoronaFade = 1
e_terrain_normal_map = 1
r_TexturesFilteringQuality = 3
r_Texture_Anisotropic_Level = 16
r_TexMaxAnisotropy = 16
sys_physics_CPU = 1
sys_physics_GPU = 0
sys_spec_Sound = 4
sys_LowSpecPak = 0
r_Beams = 4
r_BeamsDistFactor = 0.75
r_BeamsMaxSlices = 64