It *IS* an example of the fragility of Windows. Take a Linux HDD out of an Intel box, throw it in an AMD box and (assuming a generic, modular kernel) watch in amazement as it boots. Taking a stand-alone drive and attaching it to a RAID controller... well that *might* work but don't get your hopes up. And no putting an x86 build on to PPC will probably cause hilarity.
Latest version of OS X, take Intel mac drive, attach to PPC mac. Voila, it'll boot (allegedly).
Windows falls over due to a known issue, that apparently happens with a clean install from non-OEM media? That sounds like the Windows install routine can't figure it out.
But to sum up. SP3 makes random boxen go bang, MS blame HP, HP goes WTF? STFU! AMD go STFU, Intel go MUHAHAHA, MS return to assimilating lesser species... erm... fixing it sooner or later... or never.
Balmer, because DEVELOPERS, DEVELOPERS, DEVELOPERS, DEVELOPERS, DEVELOPERS!