OC and Underclock with Asus mobos

[imported_GLO]

I have an Asus P4P800 E-deluxe mobo and like most mid-hi end Asus mobo's it comes with its own OC software called AI Overclocking which lets you Overclock or underclock your PC.

I already know that OC increases CPU temps etc etc, but what i want to know is, if you underclock the PC, should the CPU temps reduce? This setting would be used for periods of inactivity? (kinda like the Pentium M chips that use speedstep to drop cpu anc clock speeds when inactive, thus increasing battery life, cpu life and case temps.

I would set this manually, but im just curious?

Thanks