Qualcomm Snapdragon 625 vs Intel Atom x5-Z8300 vs Qualcomm Snapdragon 425 (MSM8917)

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.

Intel Atom x5-Z8300

The Intel Atom x5-Z8300 is a power efficient quad-core SoC for Windows and Android devices (tablets and convertibles), which has been presented in March 2015. It is clocked at 1.44 - 1.84 GHz and part of the Cherry Trail platform. Thanks to its new 14 nanometer low-power process (P1273) with tri-gate transistors, energy efficiency has been significantly improved over its predecessor Bay Trail-T (e.g. Atom Z3795). In addition to the CPU cores, the SoC offers a DirectX 11.2-capable GPU as well as a LPDDR3 Memory Controller (2x 64 bit, 25.6 GB/s).

Architecture

The processor cores are based on the Airmont architecture, which is basically a slightly modified shrink of the previous Silvermont core. While performance per clock has not been improved, the more efficient 14 nm process leads to a better utilization of the CPU Burst (alias Turbo Boost) and a therefore somewhat higher overall performance.

Performance

Compared to the Atom x5-Z8500, the Atom x5-Z8300 is clocked slightly lower and therefore about 10 percent slower. However, the x5 still beats many ARM-based SoCs and offers a performance similar to a Qualcomm Snapdragon 801. 

Using Windows, the chip is adequate for simple everyday tasks such as light browsing or Office, but not for complex software or modern games.

Graphics

The HD Graphics (Cherry Trail) is based on the Intel Gen8 architecture, which supports DirectX 11.2 and is also found in the Broadwell series (e.g. HD Graphics 5300). With 12 EUs (Execution Units) and a clock speed of up to 500 MHz, the GPU is significantly faster as the HD Graphics (Bay Trail) and can handle at least some older and less demandig Windows games in very low settings. The GPU also supports 4K/H.265 video acceleration.

Compared to ARM SoCs, the HD Graphics offers a performance sligthly below a Qualcomm Adreno 330 or PowerVR G6430.

Power Consumption

The entire SoC is rated at an SDP of 2 watts, which indicates a TDP of less than 4 watts. Thus, the chip can be used in passively cooled tablets.

Qualcomm Snapdragon 425 (MSM8917)

The Qualcomm Snapdragon 425 (8917) is an ARM-based entry level SoC for tablets and smartphones (mostly Android based). It was announced in February 2016 and integrates four 64-Bit Cortex-A53 CPU cores (quad-core) that clock with up to 1.4 GHz. Furthermore, there is a Adreno 308 graphics card, a LPDDR3 memory controller (max. 667 MHz) and wireless radios for WiFi and 4G/LTE included in the chip.

The Cortex-A53 is the successor of the entry level Cortex-A7 CPU cores. The A53 is now capable of 64 Bit (ARMv8-ISA) and adressing more than 4 GB RAM. According to ARM the performance per MHz is a lot better and even surpasses a Cortex-A9 core.

The integrated Adreno 308 ist the integrated graphics card that supports OpenGL ES 3.0.

The integrated wireless radios support WiFi 802.11ac Wave 2, Bluetooth 4.1, GPS/GLONASS/Baidou, 2G, 3G and 4G (LTE Cat.4) standards. Futhermore, the SoC is able to decode 1080p videos in H.265 (encode only in H.264) and cameras with up to 13 MP.

The power consumption of the chip is ranging in the lower range, and therefore it is also suited for smaller smartphones. It is manufactured in 28 nm LP at TSMC.