Dell Studio 1558 processor fan on all the time with 12.1 M5

I have a Studio 1558 which has an ATI HD4500 graphics card, this machine has always had problems with the fans under OpenSuse - they run flat out until I install the Catalyst drivers. However with 12.1 M5 installing the latest Catalyst drivers (11.8) hasn’t resolved the problem and I am worried that I am going to damage the laptop. Anyone managed to overcome this problem?

The situation seems to have calmed down since the switch to Beta 1, at first problem was exactly the same as with M5 but a day or so later with no updates having been made it all settled down. Most odd.