Question about underclocking a graphics card

I have a Radeon X1600Pro and i’m using Omega drivers with ATI Tray Tools.
I made a profile for each game so that the graphics card overclocks itself as soon as I start a game.
When i’m not playing a game would it be advisable to underclock the graphics card to save on power or should I just run it at stock speeds?

Stock speeds should be fine. That’s what I do with my 1900XT.

It will use less power when not under load anyway - not sure if overclocking increases the idling power by much, though it would increase the peak load power.