The fan on my Sapphire Radeon X1600 Pro is irritatingly noisy compared to the rest of my system. I downloaded ATITool, which is meant to be the be-all-and-end-all of graphics card control, but it doesn't seem to be able to tweak the fan on the X1600, despite supporting it in other ways. Thanks go to
sixteen_bit for pointing me to
RivaTuner, which (although it's designed for nVidia cards) works admirably. My fan is now whisper-quiet, and I am no longer driven to distraction.
Contrary to the title of this post, this is not about quieting hysterical admirers...