I have recently installed Ubuntu 12.04 LTS and I keep having terrible problems with overheating which I think are caused by problems with graphics chip drivers. I have a ASUS U80V laptop supposedly with Radeon HD4570. When I check the system details the Graphics section says "Unknown". The Additional Drivers app does not offer installing any proprietary drivers. I am a rather unexperienced user when it comes to Linux, so I would appreciate any help and preferably any suggestion that my understanding would keep up to.