ACPICPUThrottle is a kernel driver for Apple MacOS X which throttles the CPU clock and voltage for generic Intel and AMD processors. It works by querying ACPI for possible clock configurations so if your BIOS doesn't think your system should be throttled, the driver will fail to load. It should work on the vast majority of standard PC laptops, including Apple's own machines.
It is licensed under the FreeBSD licence and so can be used for any purpose.
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Some Apple Mac OS X programs I have made publicly available: ACPICPUThrottle
A CPU throttling driver for Mac OS X You may find my page about installing Apple Mac OS X onto a standard PC laptop of interest
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