Qualcomm Snapdragon 808 MSM8992 vs Qualcomm Snapdragon 625 vs Qualcomm Snapdragon 615 MSM8939

Qualcomm Snapdragon 808 MSM8992

The Qualcomm Snapdragon 808 MSM8992 is an ARMv8-based high-end SoC mainly for Android tablets and smartphones. Announced in April 2014, the S808 is positioned somewhat below the faster Snapdragon 810 and startet shipping in the first half of 2015 in the LG G4 smartphone. In addition to 6 CPU cores (2x Cortex-A57 and 4x Cortex-A53), the SoC integrates an Adreno 418 GPU, a 2x 32-bit memory controller (LPDDR3-1866, 14.9 GB/s) and supports Wi-Fi (802.11ac + MIMO), Bluetooth 4.1, UMTS and LTE.

CPU

The Snapdragon 808 is based on ARM's big.LITTLE concept, which combines different CPU cores for an optimal combination of performance and power consumption. In this case, there are two fast Cortex-A57 cores clocked at up to 2.0 GHz, which offer an about 30 percent higher performance per clock compared to the previous Cortex-A15 (e.g. Tegra K1) design. Furthermore, the SoC integrates four slower, but much more efficient Cortex-A53 cores (max. 1.5 GHz), which will handle background tasks and simple applications.

All six cores can be active at the same time, although most applications aren't parallelized to support 6 cores efficiently. In many cases, the S808 will be only slightly slower than the S810 (4x Cortex-A57 and 4x Cortex-A53). Both Cortex-A53 and -A57 are based on the ARMv8 ISA and therefore 64-bit capable.

GPU

The Adreno 418 is clocked at up to 600 MHz and based on the same unified shader architecture as the Adreno 430 (Snapdragon 810). However, the Adreno 418 offers just 128 ALUs, while the Adreno 430 integrates 192 shaders. Accordingly, the Adreno 418 is about 30 percent slower and also somewhat behind the Adreno 420 (Snapdragon 805).

Nevertheless, the GPU easily handles demanding Android games and high-res displays with resolutions exceeding FullHD.

Features

The Snapdragon 808 offers numerous wireless technologies such as Bluetooth 4.1, WLAN 802.11a/b/g/n/ac + MIMO as well as a dual-SIM cellular modem supporting LTE cat. 6 (up to 300 Mbps), WCDMA, CDMA, EV-DO, TD-SCDMA and GSM/EDGE.

The SoC can encode and decode 4K videos using dedicated hardware. A large number of video codecs including H.265 (for decoding) will be supported. The dual ISP can handle cameras with up to 55 MP.

Power Consumption

Thanks to a new 20 nm process (TSMC), the energy efficiency has been improved noticeably compared to its 28 nm predecessors. This allows higher performance while keeping power consumption on roughly the same level. Depending on the field of application, the maximum power consumption should be about 3 W for smartphones and 4 W or greater for tablets. However, 14 nm SoCs as the Samsung Exynos 7420 offer even better energy efficiency.

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 615 MSM8939

The Qualcomm Snapdragon 615 MSM8939 is a mid-range ARMv8-based SoC largely for Android tablets and smartphones. Announced in February 2014, the S615 is one of the first 64-bit capable SoCs from Qualcomm. In addition to 8 Cortex-A53 CPU cores at up to 1.7 GHz, the SoC integrates an Adreno 405 GPU with a 2x 32-bit memory controller (LPDDR3-1600, 12.8 GB/s) and supports Wi-Fi (802.11ac), Bluetooth 4.0, UMTS, and LTE.

CPU

The Cortex-A53 is the successor to the very popular Cortex-A7 design. In addition to the new 64-bit capable ARMv8 ISA, the cores offer a variety of other improvements such as better branch prediction. This leads to a significantly higher performance per clock, which is even above the older Cortex-A9.

The eight cores of the Snapdragon 615 are divided into two quad-core clusters, each optimized for a different operating point. While one cluster can clock up to 1.7 GHz to handle more demanding applications, the other cluster is limited to a maximum of 1.0 GHz for energy-saving purposes. All eight cores can be active at the same time, although most applications aren't parallelized to support 8 cores efficiently.

Overall, the Snapdragon 615 offers a performance similar to that of the older Snapdragon 600 (Krait architecture).

GPU

Another new feature is the integrated graphics unit named Adreno 405 (550 MHz). The Adreno 400 series has been substantially redesigned and supports DirectX 11.2 (FL 11_1) including hardware tessellation, OpenGL ES 3.1, and OpenCL 1.2. Furthermore, the performance has been significantly improved, which is now similar to the Adreno 320 and PowerVR G6200.

Features

The Snapdragon 615 offers numerous wireless technologies such as Bluetooth 4.0 and WLAN 802.11a/b/g/n/ac as well as a Multi-SIM cellular modem supporting LTE cat. 4 (up to 150 Mbps), WCDMA, CDMA, EV-DO, TD-SCDMA and GSM/EDGE.

The SoC can encode and decode 1080p videos using dedicated hardware and stream content to displays with up to 2560 x 2048 pixels. A large number of video codecs including H.265 (playback only) will be supported. The camera ISP can handle sensors with up to 21 MP.

Power Consumption

The Snapdragon 615 is manufactured by TSMC in a 28 nm LP process. According to the specifications, we expect a medium or medium-high power consumption for use in medium-sized or larger smartphones and tablets.