Apple Inc.’s (AAPL) A8X Chip Is Even More Impressive Than Expected

When it was first leaked that Apple's (AAPL 1.27%) iPad Air 2 would feature an upgraded version of the A8 processor known as the A8X, I had speculated that it would be the same chip, but perhaps with a beefier graphics block and a slightly higher-clocked CPU complex. In fact, I even went so far as to provide performance estimates based on Apple's given performance numbers.

However, it looks like I was wrong. The A8X chip is far more impressive than I had initially thought.

Say hello to three faster CPU cores
While I have long been a proponent of "fewer but faster" processor cores in mobile devices, particularly as it is very difficult for programmers to utilize multiple cores, I'd never be unhappy with more cores as long as those cores are faster than what came before. And that's precisely what Apple did with A8X.

The A8X features three of the same CPU cores found in the Apple A8 -- rather than the two found in the A8 -- but it also runs those cores at a maximum of 1.5 GHz rather than 1.4 GHz as found in the A8. This means that the A8X is not only faster than the A8 in programs that can only use one or two cores, but for those applications that can use more cores, it's faster still.

Apple has built what appears to be, at least according to the performance tests that Engadget published of the iPad Air 2, the fastest mobile system-on-chip available today in CPU performance.

The graphics performance is much improved
Engadget also ran a number of graphics performance tests. In the GFXBench 3.0 "Manhattan" test, the iPad Air 2 scores 32.4 frames per second in the "off-screen" test. This means that all devices render at the same resolution, so the numbers are comparable across devices. This was about 2.5 times the performance of the A7 chip in the iPad Air. Further, it even managed to edge out the NVIDIA (NASDAQ: NVDA) Shield tablet, powered by NVIDIA's Tegra K1 processor, which scored 31 frames per second.

Will Apple move its Macs over to the A-series?
Every time Apple comes out with some impressive new silicon, the question of whether Apple will actually move its Mac lineup to these chips -- away from Intel's (INTC 0.64%) -- comes up. Interestingly enough, it's worth seeing how close Apple's A8X is to a MacBook Air in a well-known performance test. Note that no benchmark is perfect -- and Geekbench does garner its share of criticism among the technical community -- and that the entire purpose of this exercise is to get a "rough" idea of what's going on.

Using numbers from the Geekbench database, we can try to get a rough idea of how the Core i7 4650U in the 2013 MacBook Air compares with the A8X inside of the iPad Air 2:

Source: Geekbench database (Primate Labs).

It looks as though Apple would still need to improve the per-core performance -- as measured by Geekbench -- of its chips by about 63% to catch up with the Core i7 inside of the MacBook Air. Further, when Intel launched its Broadwell-based Ultrabook processors, Intel claimed that it would see a ">5%" improvement in per-clock performance. On top of that, I wouldn't be surprised if Intel were able to boost the clock speeds slightly with the new parts, as the 14-nanometer process should provide nice performance and power improvements.

There's no doubt that Apple's chip teams are putting out some pretty seriously impressive stuff. However, I'm not convinced that Apple will want to divert its engineering resources to trying to build a Mac-focused chip, because Mac unit sales are just a small fraction of iPad/iPhone sales. Additionally, Apple would need to transition from the X86 architecture to the ARM (ARMH) architecture for MacOS.

Apple has successfully transitioned architectures before; but unless there's a really good reason to do it, I don't think Apple would go through the hassle.

New Apple products to come?
I can't help but be impressed with what Apple has been doing in the mobile chip space. The company has been hiring top-notch talent from across the semiconductor industry, with Apple chip engineers hailing from prestigious semiconductor powerhouses like Intel, ARM, IBM, and many others.

I think we aren't even close to seeing what Apple's chip teams are capable of. That, to me, is incredibly exciting.