Microsoft originally released Tweak UI as a value add tool with Windows 98. Since then, its popularity has grown and its usage expanded, and with it, its power as well. Today, Tweak UI is the best tweaking tool out there for the important changes, and Microsoft has refused to provide official support for it. While that is not an issue, i.e. there are hundreds of support websites on the web, the fact that Microsoft has not yet released a version compatible with the ever-growing true 64-bit PC's, starting with the AMD series and the upcoming Intel series.
So, if you are looking for Tweak UI for AMD 64-Bit processors or Windows 64-Bit Edition, download it here!