Could you make your G5 faster at the touch of a button? According to recently released IBM documentation for the PowerPC 970FX (used in Dual 2.5GHz PowerMacs, Xserve G5s and iMac G5s), the second-generation 90-nanometer G5 uses a set of "soft PLLs" to determine its clock speed (and therefore that of the main bus, which is 1/2 CPU speed, or 1/3 in recent 1.8GHz 970FX systems).

Theoretically, it should be possible to manipulate these settings from a software application; in fact, we've contacted a few developers who are looking into that possibility. We encourage other parties to do the same! Similar overclocking tools have been available for ATi Radeon graphics cards, and IBM 750FX/GX (G3) processors for some time, and there is no shortage of speed freaks who'd like to squeeze a few hundred million extra Hertz out of their G5's, that's for sure....