Read http://www.tomshardware.com/mobile/20030212/mobile_pentium-03.html and you may soon realise that what you ask is not in this hardware.
What I would do is to triple check for spyware, trojan, virus, worm or other damage since I find such to keep the CPU busy and as such the sleep or napping of the CPU never happens.
Bob
My notebook is overheating, thus i raise my laptop to increase ventiliation. but it isn't much help, so i turn to underclocking, which does decrease fan activity. however, my underclock untility is crappy. i want my cpu to run at 50% but it sets my cpu to run at 75%. in other words, the cpu underclocking utility is not accurate. i would like a free underclocking utility that can do its job well. Any recommendations?
System Spec: 1.8 Ghz Pentium 4-M, 768mb RAM, 32MB ATI Mobility Radeon 7500, laptop model ASUS L3C.

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