ET FPS Problem <3

I've recently bought myself a new screen (and therefore sacrificed all my musclememory, but that's not the essence of the problem here), and I've kind of noticed that going up from 1680x1050 to 1920x1080 did NOT lower my FPS. I usually have around 80-100 in open areas and stable 125 in corridors. For a little test, I went down to 1280x1024 and the FPS did not change.

My renderer settings:

"seta r_allowExtensions 1
seta r_ati_fsaa_samples 0
seta r_ati_truform_normalmode GL_PN_TRIANGLES_NORMAL_MODE_LINEAR
seta r_ati_truform_pointmode GL_PN_TRIANGLES_POINT_MODE_LINEAR
seta r_ati_truform_tess 0
seta r_cacheshaders 1
seta r_clampToEdge 1
seta r_clear 0
seta r_colorbits 32
seta r_colorMipLevels 0
seta r_customaspect 0
seta r_customwidth 1920
seta r_customheight 1080
seta r_depthbits 24
seta r_detailtextures 0
seta r_displayRefresh 85
seta r_dlightBacks 1
seta r_drawfoliage 0
seta r_drawSun 0
seta r_dynamiclight 0
seta r_ext_ATI_pntriangles 0
seta r_ext_compiled_vertex_array 1
seta r_ext_compressed_textures 1
seta r_ext_gamma_control 1
seta r_ext_multitexture 1
seta r_ext_NV_fog_dist 0
seta r_ext_texture_env_add 0
seta r_ext_texture_filter_anisotropic 0
seta r_facePlaneCull 1
seta r_fastsky 1
seta r_finish 0
seta r_flares 0
seta r_fullscreen 1
seta r_gamma 3
seta r_glDriver opengl32
seta r_glIgnoreWicked3D 0
seta r_highQualityVideo 0
seta r_ignoreFastPath 0
seta r_ignoreGLErrors 1
seta r_ignorehwgamma 1
seta r_inGameVideo 0
seta r_intensity 1.5
seta r_lodbias -999
seta r_lodCurveError 250
seta r_lodscale 5
seta r_mapoverbrightbits 1
seta r_mode "-1"
seta r_normallength 0.5
seta r_nv_fogdist_mode GL_EYE_RADIAL_NV
seta r_oldMode ""
seta r_overBrightBits 1
seta r_picmip 3
seta r_picmip2 0
seta r_primitives 0
seta r_railCoreWidth 1
seta r_railSegmentLength 32
seta r_railWidth 16
seta r_rmse 0.0
seta r_roundImagesDown 0
seta r_simpleMipMaps 0
seta r_smp 0
seta r_stencilbits 0
seta r_stereo 0
seta r_subdivisions 20
seta r_swapInterval 0
seta r_textureAnisotropy 1.0
seta r_texturebits 32
seta r_textureMode GL_LINEAR_MIPMAP_LINEAR
seta r_trisColor 1.0 1.0 1.0 1.0
seta r_uifullscreen 0
seta r_wolffog 0"


My PC specs:
CPU: AMD Athlon x64 Dualcore 2.69GhZ
RAM: 3,25GB
GPU: GeForce GTX 275

Do not think any more hardware specs are relevant to my FPS, if yes, tell me and I'll fill them up. In fact, I think this comp should be way more than enough to have 125 stable everywhere since I have 250 stable on CoD4 with Full HD resolution.

So does anyone have an idea why my FPS are not 125? Thanks for your help :)

//edit: Threaded optimisation is off, still falls to 90~100. There must be another reason too.