The headline pretty much says it all, except it rather skips the point that MacOS X is still booting. See, he had to install Linux on his Centris and then run PearPC to emulate a PowerPC process capable of booting OS X. As a result, he’s running about the equivalent of a 0.5mhz G3.
I wish I still had my overclocked Quadra 840AV (overclocked from 44mhz to 48mhz!), that would cut a day or so off his boot time.