Quote:
The speed of 7447 CPU chip is defined by logic levels of its five PLL_CFG pins. This sets Bus-to-Core multiplier that together with bus (SYSCLK) frequency produces CPU core clock. These pins have internal pull-up resistors so the CPU clock in practice is set by leaving each pin either floating or grounded with zero Ohm resistor (call them jumpers if you wish).
In english, that means the clock speed of the Mac Mini's processor is setup in a very similar way to the old bridge tricks used on Athlons. Join the right contacts and you can set the speed yourself. Easy stuff if you know a tiny bit about electronics and can use a soldering iron... and you're willing to void your Mac Mini's warranty.