Which is even more why Microsoft should have insisted on chipsets installed on manufacturers PCs that were capable of the 'full' Vista experience .. or look to AMD in the short term.
It rendered the Vista 'update anytime' to useless. If you bought a 'Vista capable' PC with 'Basic', then you could upgrade to 'Premium', but the PC would revert to basic. ie Not Aero, etc.
(Anyway after the 915, the 945 chipset didn't prove the best either!)
