Readers familiar with the semiconductor landscape might crucify me for comparing Apple's (NASDAQ:AAPL) A8 processor, which goes into svelte, 4.7-inch and 5.5-inch smartphones, respectively, with a high-end tablet processor from Intel (NASDAQ:INTC) which is destined to go into fairly large (but also fanless) tablets and 2-in-1 convertibles.

Indeed, while I don't wish to take away from Apple's fantastic technical achievement with the A8, I do intend the following article to be a sanity check against the tired claims that Apple's A-series chips are currently good enough to boot Intel out of products such as the MacBook Air and the MacBook Pro.

Looking at CPU performance
Interestingly enough, if we look at the test scores of a benchmark known as Geekbench 3, the A8 and Intel's Core M aren't exactly all that far apart:

SoC

Geekbench 3 64-bit Single Core

Geekbench 3 64-bit Multicore

Core M 5Y10a @ 2GHz

2064

4249

A8 @ 1.4 GHz

1620

2906

Sources: tabec.com, author measurements.

However, while Geekbench 3 seems to be one of the only "pure" cross-platform CPU benchmarks, I have seen very polarizing views of the test's utility as a true measure of general purpose performance.

So it's probably helpful to look at CPU performance in context of more "real world" applications. In this case, let's look at the 3DMark Physics test, which is a very intense CPU test that probably mirrors some of the more difficult computations that a mobile device will need to perform -- physics in games.

SoC

3DMark Physics

Core M 5Y70a @ 2.6GHz

33663

A8 @ 1.4 GHz

9658

Hypothetical A8 @ 2.6 GHz

17963

Sources: author measurements and estimates, Legit Reviews.

In this test, there's no contest -- the Core M is substantially faster than the A8. In fact, even if we assume perfect performance scaling with clock speeds, scaling the A8 up to 2.6 GHz still doesn't yield performance numbers comparable with what Intel is able to deliver with Core M, albeit in a larger tablet form factor.

How about graphics performance?
Luckily for us, 3DMark also measures graphics performance. Here's how the A8 and the Core M do in the graphics sub-score:

SoC

3DMark Physics

Core M 5Y70a @ 2.6GHz

51376

A8 @ 1.4 GHz

24202

Sources: author measurements, Legit Reviews.

Looks like Intel's Gen. 8 graphics block in Core M is over twice as fast as the graphics processor inside the Apple A8.

A8 isn't MacBook-worthy
It is unlikely that the Core M will fit particularly well into a smartphone; the A8 integrates far more in terms of non-CPU and non-graphics blocks to make it suitable for that purpose than Core M does. However, for PCs and 2-in-1 convertibles, Core M is clearly the superior product.

Intel really does get a lot of mileage from its experience in developing high-performance notebook and desktop-oriented processors, and it certainly benefits from the superior transistor performance afforded to it through its 14-nanometer process.

Frankly, with the foundries effectively two steps behind Intel at this point in terms of manufacturing technology (Intel is on its second-generation FinFETs; Taiwan Semiconductor and Samsung are just getting 20-nanometer planar out the door), it's hard to imagine that Apple would be able to substitute Intel's chips for custom-designed processors in its Mac lineup.

However, the A8 really is a fantastic mobile processor, particularly as it integrates much of the key functionality outside CPU and graphics to drive an optimal smartphone experience that Intel's Core M does not.

Foolish bottom line
At this point, I would still be wary of any claims that Apple will be replacing Intel in any Mac products anytime soon. The performance delta is still pretty large between what Intel can do for fanless 2-in-1s and clamshells and what Apple has done for its iPhone and iPad chips.

As much as Apple loves vertical integration, I doubt it would cut Intel out and, in turn, significantly hamper the competitiveness of its Mac products relative to the competition.

Ashraf Eassa owns shares of Intel. The Motley Fool recommends and owns shares of Apple and Intel. Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.