MediaTek Helio X27 MT6797X vs Qualcomm Snapdragon 625 vs Qualcomm Snapdragon 435

MediaTek Helio X27 MT6797X

The Mediatek Helio X27 MT6797X is an upper mainstream ARM SoC for smartphones (mainly Android based). It is manufactured in a 20 nm process and is equipped with 10 CPU cores. Two fast Cortex-A72 cores are running at up to 2.6 GHz (performance), four Cortex-A53 cores at up to 2 GHz (balanced) and four Cortex-A53 cores at up to 1.6 GHz (efficiency). All cores support 64-bit and the utilization of three clusters is supposed to improve efficiency according to Mediatek. The two A72 cores are only designed for short "Burst-Performance scenarios" according to Mediatek and are probably not used for sustained workloads. Compared to the similar named MT6797, the MT6797X was introduced later and offers higher clock speeds for CPU and GPU.

The integrated ARM Mali T880 MP4 (according to Wikipedia) GPU is clocked at up to 875 MHz and has four cluster (from 16) from the Midgard (4th Gen) architecture.

The chip also includes an LTE modem (Cat. 6 300/50 Mbps, DC-HSPA+, TD-SCDMA, EDGE, CDMA2000, ...) as well as a WLAN 802.11ac (280 Mbps) modem. GPS/Glonass/BeiDou is supported for location. The integrated video encoder can handle up to 4Kx2K H.265 at 30 fps and HDR. The SoC can also decode H.265, H.264 and VP9 in 4K30. 

Power Consumption

The processor is manufactured in a 20 nm process at TSMC and should have an average power consumption under load.

Qualcomm Snapdragon 625

The Qualcomm Snapdragon 625 (SD625) is a mid-range octa-core SoC with eight ARM Cortex-A53 cpu cores at up to 2 GHz, an Adreno 506 GPU, a DDR3L-1866 memory controller and a X9 LTE (Cat 7, 4G+, 300 Mbps down, 150 Mbps up) modem. Furthermore, the chip supports 802.11ac WiFi and Bluetooth 4.1. It is manufactured in 14nm FinFet. The processor performance should be similar to a HiSilicon Kirin 650, which also offers 8 Cortex A53 cores at up to 2 GHz. However, due to the modern manufacturing process, power consumption and throttling should be better with the Snapdragon 625.

Qualcomm Snapdragon 435

The Qualcomm Snapdragon 435 (SD435) is a lower mainstream SoC for (Android based) smartphones and tablets. Contrary to the Snapdragon 630, it is still manufactured in a 28-nm process and also consists of an octa-core CPU part with ARM Cortex-A53 cores. However, they are only clocked at up to 1.4 GHz. The integrated X9 LTE modem supports Cat. 4 with maximum transfer rates of 300 Mbps (downstream) and 100 Mbps (upstream). The SoC also includes an Adreno 505 GPU with support for Vulkan and OpenGL ES 3.1. WiFi 802.11ac and Bluetooth 4.1 are supported as well. The memory controller supports LPDDR3 clocked at 800 MHz (so probably dual-channel DDRL-1600). The main difference to the Snapdragon 430 is the faster LTE modem.