While building systems with AMD processors, a 350W PS is higly recommended, as the AMD is very demanding in Currents... I suggest you buying a High Quality one, so that you can use its outputs to supply a very demanding system (eg many HDs, drives and SCSI peripherals). You can get an Addtronics PS (highly recommended by AMD), but it will cost about 90 Euros... Check h**p://w*w.addtronics.com for more info.
Now, cooncerning the temperature, since AMD processors are more overloaded than INTELs, they are in higher temperature levels. If you have a good Fan and Heatsink supplied, there is no problem at all. For high quality coolers, check h**p://w*w.globalwin.com, or h**p://w*w.spire.nl for HQ budget ones... I hope I answered your questions properly.