yeha.. that definately looks like a GPU issue. you can get a similar effect if you crank down the LOD Bias too much (maybe it was positive bias.. forget which direction pulls the lower quality textures closer to your view plane). If it's running hot, it is likely underpowered for the game--or at least marginal. Might want to get an active cooling pad (one with a fan to pull heat away from the laptop) to help cool it down. Might help with the glitching when it overheats.