I've had my Mac mini throttle down to 180Mhz under Linux (due to incorrect ACPI settings), to the point where I could see the window elements being drawn :) So

I've had my Mac mini throttle down to 180Mhz under Linux (due to incorrect ACPI settings), to the point where I could see the window elements being drawn :) So at least that generation Intel was capable of pretty extreme downclocking.