Its the graphics card, a 5 second google would have avoided a spam post in a thread Scawen is most likely email notified to.
Same bug for me, also - I'm having some LOD issues. Even though I have all my settings to the max, I get quite dramatic object spawning infront of me, if I'm at one end of the westhill straight and start to drive down it, the fence appears around me and the objects such as cones and tires by the track also appear.