I've a Mac Pro1,1 (2.66GHz) Without any hardware changes it has suddenly started taking over half an hour to boot. This is both booting to HD and to DVD. The Apple hardware test (despite taking hours), finds no fault. Condition remains with all HDs including boot HD, removed and booting to DVD. Once booted everything runs at this very slow pace. e.g. it will take 5 minutes of mouse manipulation to get it over an icon. Tech Tool will not run. (Underlying process error). Any ideas?