MediaTek, best known for their ARM processors found in low-end and mid-range smartphones, has announced they have developed the world's first true octa-core chip based on the ARM architecture. Unlike Samsung's Exynos 5 Octa, which has eight cores but uses ARM's big.LITTLE configuration so only four cores are ever used at once, MediaTek's octa-core CPU will be able to use all eight cores simultaneously.
Not many technical specifications were revealed by MediaTek in their announcement, although going by previous leaks we can gather some extra information. The MT6592 will feature a 28nm eight-core ARM Cortex-A7 CPU clocked between 1.7 and 2.0 GHz, with an unspecified GPU and radios that support up to HSPA+ mobile networks; no LTE modem has been included in this chip.
Perhaps the most critical piece of information about the MediaTek MT6592 is that it uses all Cortex-A7 cores for CPU tasks, as opposed to Cortex-A15 cores seen on its competitors. While the A7 cores have the same architecture and feature set as the A15 cores, the A15s are around twice as powerful: A7 cores deliver 1.9 DMIPS per MHz, while A15 cores can deliver up to 4.0 DMIPS per MHZ. This means that in applications that only use a few of the processor's cores, an A15-based chip has a significant advantage in processing power.
However, when looking at multi-threaded performance and power consumption, it's possible that the MediaTek CPU using all eight cores could deliver similar performance and battery life to a quad-core Cortex-A15 processor with the same clock speed. In graphs provided by MediaTek, they show an eight-core CPU clocked at 2.0 GHz delivering equal power efficiency compared to a 2.0 GHz quad-core processor while decoding video, with twice the performance. It remains to be seen how accurate this is in real world situations.
MediaTek's octa-core processor is set to become available in the last quarter of this year to OEMs, with an array of less popular smartphone manufacturers (Lenovo, Acer, ZTE, etc.) likely to adopt the chips in their middle-tier devices.