The revolutionary iPhone 6 and iPhone 6 plus made their entry in the later 2014 and till then the time of Apple has changed. In past two years, Apple has to struggle in the market because of the Android rivals but the recent released report of Apple profits has shown that king is back in the action and the reason is only the launch of iPhone 6 and iPhone 6 Plus.
The iPhone 6 is powered with the A8 chip designed at 20nm scale. And new chip promises a reduction in heat or increase in productivity, which in turn can be due to higher clock speeds or add new computational units on the crystal. Judging from the data, which unveiled Apple, A8 increasingly moved towards performance than economy. Namely, it is stated on CPU speed increase to 25% and GPU – 50% compared to A7. The gain obtained by increasing the number of transistors: 1 billion to about 2 billion. However, the high density of transistors on a progressive process technology was used in part to reduce the size of the crystal: from 102 to 89 mm compared with Apple A7. Apple, as usual, very few reports on the technical characteristics of SoC and this time nothing at all – its architecture.
In Apple A8 CPU used the original design, which differs little from Cyclone –architecture of cores in Apple A7. Cyclone, as well as its improved version, work with a set of instructions ARMv8 Arch64, and thus, is a 64-bit CPU. Cyclone is a core of “wide” superscalar processor capable of receiving the performance 6 instructions per clock cycle. Due to this property Cyclone achieves high performance at a relatively modest frequencies, providing a high ILP (instruction-level parallelism) executable code. In A7 and A8 has two processor Cores, operating at frequencies of 1.3 GHz and 1.4 respectively. And now rumours suggest that Apple will launch the upcoming iPad Air 3 with special A8X with triple core chip.
Let’s back to the iPhone. For comparison, system of Qualcomm Snapdragon 801, which is equipped with the flagship devices on Android, has a frequency up to 2.5 GHz, but it takes only 3 instructions per clock cycle per core. The same applies to NVIDIA Tegra K1, consisting of 4-licensed core ARM Cortex-A15, operating at frequencies up to 2.3 GHz. Since the high frequencies are already providing competitive single-threaded performance, Qualcomm and NVIDIA products have an advantage over SoC Apple as two cores, but real-world applications for mobile operating systems to date have not yet learned to use a mass number of threads. As we will see in the benchmarks, Apple A8 feels very confident in the confrontation with quad core system on chip rivals. In addition, the high frequency of the CPU is a high voltage, causing increases and power consumption. And Apple engineers have done really great with the A8 chip of new iPhone 6.