--- Operating System, Graphics card ---
Win7 64 Nvidia gtx

--- Blender version with error, and version that worked ---
2.66


--- Short description of error ---
There is an interesting bug with texture nodes. it creates a noisy look to the nodes in use. I thought that it was a Cycles related issue however it can be repeated with the internal as well so it must be independent from the renderer. I am not sure how to describe this issue, I think best is to check the screenshot and the sample scene attached. When you open the scene make sure you are viewing the compositing nodes

--- Steps for others to reproduce the error (preferably based on attached .blend file) ---

Load the attached scene, press render. And make sure to check the attached screenshot.