But would be a lot slower than the move from PowerPC.
Apple had worked on shifting OS X from PowerPC to Intel chips from the earliest days of the OS. Apple had a special ‘what if’ department working on what things they could and may have to do.
There will have been many reasons Apple shifted from the PowerPC but the main reason was mobile. Not tablets and phones, but laptops. They couldn’t make a G5 laptop. I remember being the proud owner of a G4 Aluminum 17 inch PowerBook and it’s only failing was a lack of pace in some regards. The problems came when the G5 processor was put in to a confined space it got hot. Really hot. I had a few PowerMac G5s in my time and when it came out, it was packing about 8 fans. When in test mode the tower sounded like it was going to take off.
When I started using the iMac G5s this issue was immediately noticeable. The large vent on the back would create a heat haze after a day’s full use. (Stopped people leaning on them right enough!) This issue of heat and power drain meant that Apple couldn’t chase the laptop market. Enter Intel. We got the first MacBook Pro 15 inch with an Intel Core Duo and the rest of the line followed thought the space of a year.
With the MacBook Air, Apple pushed the boundary of what was achievable in the laptop space and created something that became the new yard stick. Now, what ever exclusivity Apple had negotiated with Intel has come to an end and other manufacturers are farming out Ultrabooks in their best ‘not a MacBook Air’ disguises. Apple wont mind this, as now Bob Mansfield is back in the picture, the future of Apple’s ultra mobile offerings is looking in-house.
There have been rumors (surprise, surprise!) of MacBook Air prototypes running with Apple A series processors in them. I can put a bit of stock in this, given that OS X runs on this hardware with little alteration. Given that it is a laptop all about being the pinnacle of ‘what a laptop can be’, power savings from more efficient chips would allow for high density graphics (there’s a chip for that in every 3rd and 4th gen iPad) and battery life that could stretch for days, not hours.
ARM recently announced a 64-bit architecture. This will allow for copious amounts of RAM, as the prices of that memory is falling in price and growing in efficiency. After all things considered, there is one more thing to think about.
For the last decade or so, the march of development has lead to multi core processors. Dual core, to Quad core becoming common place and high performance machines getting Hexa core and Oct core chips, some times in dual configuration. If Apple were to have a tighter control over the price per core, they could build desktop machines with 32, 64 hell 128 cores. OS X could take it and speeds would be eminence. Now that is conjecture, but I’d love to be right on that one!