I was really hoping this would have been fixed eventually, but in addition to enabling support for automatic processor/fan throttling in your BIOS, you must also configure Windows to use these features. In the "Power Options" (not sure what it's called in Windows 7) in the control panel, you need to set the power scheme to "Minimal Power Management." Different power management profiles enable different strategies for throttling hardware into lower power states in about the most non-obvious way possible. Anyway, I hope that works for you. (This also applies to Windows XP. Not sure about Windows 2000, though.)