I've got a chance to pick up a 12" PB G4 1.33GHz (A1010) for under $400. The catch - it chimes, boots to the grey screen, minus the Apple, then freezes. In my experience, 9 times out of 10 zapping the PRAM or resetting the PMU fixes a problem like this. However I've heard stories of people who've needed to replace the whole MB under the same circumstances. The owner tells me there are no beeps and the hard drive isn't grinding or making any other horrible sounds. With this limited amount of information, what are the odds it's the board?