Apple has unleashed a new iPhone to select developers in a sort-of preview of what's to come in the company's to-be-released iPhone 5. Unofficially dubbed the iPhone 4S, the smartphone look and feels just like a standard iPhone 4, but with one major difference: Instead of an A4 chip nestled within the device's insides, Apple's plopped in its dual-core A5.
According to a report from 9to5 Mac, this iPhone "4S," as certain developers have nicknamed it, is completely indistinguishable from a standard iPhone 4. The only differences being that the iPhone 4S comes with the A5 chip, as mentioned, and that it must be locked in a developer's safe each evening.
So what's the big difference between Apple's A4 and A5 anyhow? Well, the most obvious difference is that it's a move from a single-core ARM A8 design to a dual-core ARM A9 processor. The A9 processor runs a variable clock speed of around 900 MHz on average and comes with double the L2 memory of its predecessor chip–an increase from 512 KB to one full megabyte.
A new graphics processing unit–the dual-core PowerVR SGX 543MP2–replaces the single-core PowerVR SGX 535 found in Apple's A4 chip. The extra core provides the basis for Apple's claims that the iPad 2—which sports an A5 chip to the iPad's A4–offers nine times the graphical performance of its predecessor.
"Architecturally the 543MP2 has more than twice the compute horsepower of the SGX 535 used in Apple's A4," writes AnandTech's Anand Lal Shimpi. "Each shader pipeline can execute twice the number of instructions per clock as the SGX 535, and then there are four times as many pipes in an SGX 543MP2 as there are in a 535. There are also efficiency improvements as well."
Although Shimpi was unable to replicate Apple's claims of nine times the graphical gains between the iPad and the iPad 2, he did find a range of three to seven times the performance in frames per second depending on the specifics of the GLBenchmark 2.0 testing being run.
As for the iPhone "4S," we should note that there's no indication that this is the actual setup Apple will be sticking with, design-wise, when it finally unveils the iPhone 5 to the masses. After all, the prototype phone even runs iOS 4; it's highly likely that Apple's next iPhone will ship tangentially with the company's fifth-generation mobile OS release.
Nevertheless, you can mark this one off on your Apple rumor charts: If 9to5 Mac's source speaks true, then the next iPhone is going dual-core. Only 341 more rumors to go!