I have it working perfectly well on my rig which is Win7 64bit @ 5760x1080.
What version are you running?
Is it a steam based game?
This is the contents of my graphicsconfig.xml file.
Code:
<?xml version="1.0" ?>
<Reflection>
<class name="BRTTIRefCount" base="root class" />
<class name="BPersistent" base="BRTTIRefCount">
<prop name="Name" type="String" />
</class>
<class name="GraphicConfigData" base="BPersistent">
<prop name="Mode" type="Fct" />
<prop name="Vsync" type="Fct" />
<prop name="Windowed" type="Fct" />
<prop name="TextureFilter" type="Fct" />
<prop name="TextureResolution" type="Fct" />
<prop name="Brightness" type="Fct" />
<prop name="CarDetailLevel" type="Fct" />
<prop name="TrackDetailLevel" type="Fct" />
<prop name="ShadowDetailLevel" type="Fct" />
<prop name="MotionblurLevel" type="Fct" />
<prop name="EffectsDetailLevel" type="Fct" />
</class>
<data class="GraphicConfigData" id="0xBBF320">
<prop name="Name" data="" />
<prop name="Mode" adapter="0" width="5760" height="1080" antialias="8" refresh="60" />
<prop name="Vsync" vsync="0" />
<prop name="Windowed" windowed="0" />
<prop name="TextureFilter" texturefilter="5" />
<prop name="TextureResolution" textureresolution="2" />
<prop name="Brightness" brightness="10" />
<prop name="CarDetailLevel" cardetaillevel="2" />
<prop name="TrackDetailLevel" trackdetaillevel="2" />
<prop name="ShadowDetailLevel" shadowdetaillevel="3" />
<prop name="MotionblurLevel" motionblurLevel="2" />
<prop name="EffectsDetailLevel" effectsdetaillevel="2" />
</data>
</Reflection>
Using ATI drivers 11.6, Nvidia Drivers 280.26, PhysX Version 9.10.0514 + hybrid physx mod.