Apple (AAPL -1.22%) engineers are "confident" that the custom-designed ARM-based chips which now run the iPhone and iPad will one day be powerful enough to run Mac laptop and desktop computers, Bloomberg reported after talking to three people in the know who wish to remain anonymous.

If so, that would mean a move away from the Intel (INTC -2.40%) chips that have powered Apple's Mac line since 2005. That chip-change from the IBM-produced (IBM 0.06%)PowerPC processors was a major change for Apple, but it gave Mac users the ability to run Microsoft's (NASDAQ: MSFT) Windows operating system on the same computer that ran OS X.

So, what would another CPU change do for Apple?

It would create the basis for a more consistent operating environment across its full line of computers, phones, and tablets. As British-based ARM Holdings (ARMH) is producing the 64-bit processors upon which Apple has based its A5, A6, and A6X chips, that is now possible.

The ARM chip architecture also uses less power than the Intel chip design. That translates to cooler-running devices. Energy efficiency and less heat for Mac laptops were major reasons Steve Jobs pushed for the transition from Power PC chips to Intel chips.

And what could such a change mean for Intel?

It certainly wouldn't be a good thing, especially with the sluggish demand for Windows computers already acting as a sea anchor on Intel's sales as well as those for chip maker AMD (NYSE: AMD).

And what Apple does is often emulated by others. If Apple eventually makes the ARM jump, a follow-the-leader game could prove devastating to makers of other chips.

Recent developments of the personnel-type might also come into play regarding the future of ARM-based Macs. The resignation last week of Scott Forstall, Apple's head of iPhone software development, may open the door a bit further for ARM development.

Bob Mansfield, the head of Apple's newly formed technologies group, has been looking into different chip designs but did not have any sway over the software writing specialists who then worked for Forstall. Bloomberg reports a source saying that Mansfield was interested in combining iOS and the Mac, while Forstall's was focused on iOS for Apple's mobile devices. That potential impediment to ARM development is now gone.

But Intel has had a good seven-year run with Apple, and even if Apple is successful with a new ARM design for its Macs, a processor change and the mandatory rewriting of software to run on the new chips that such a change would require -- not to mention the development of translation software to allow older software to run on the new chips -- would push any such changeover well down the road.

By that time, a company like Intel, which has made large investments in new plants and research and development, could have some new tricks up its own sleeve.