TurionPowerControl is a nice command line tool for Windows and Linux that allows users to tweak AMD processors parameters. It is available in both 32 bit and 64 bit versions.
It currently supports
Included with the package you will download there's a complete documentation (inside the doc folder) that will teach you how to use it
Latest experimental version available is v0.43, updated 2012/04/17: Download TurionPowerControl v0.43
Older versions are available here:
There is also a project archive that will compile with Microsoft Visual C++ 2008. It is a very old version BTW: