The specs for the Exynos 7 Octa (7580) has been added below and you will note that it has lower specs than the Samsung Exynos 7 Octa (7420). You will also note that the chip is more in line with the Exynos 7 Octa (7870) as there is no secondary processor or for that matter a lower spec face camera. You can compare the two processors below based on their specs.
Exynos 7 Octa (7580) Specs
The Exynos 7 Octa (7580) was made on the older 28nm HKMG production 
process so it will not be as power efficient as other processors in this series or the other series made after these ones. The primary CPU is a Cortex-A53 1.6GHz Octa (eight powerful 1.6GHz 64-bit CPU cores) with a Mali-T720 MP2 GPU and this is a bit slow compared to what came afterwards as it has the ability to run full HD at 30fps. The screen resolution is a WUXGA (1920×1200) with a 16MP rear camera as well as a 5MP face forward camera. The LTE connectivity is standard for this range of mobile phone where you will find it in with 300Mbps (DL) / 50Mbps (UL) speeds. The memory is also slower at LPDDR3 800MHz which may make the video quality and phone speed a bit slower.
| SPEC | Exynos 7 Octa (7870) | Exynos 7 Octa (7580) |
|---|---|---|
| Series | Exynos 7 | Exynos 7 |
| Process | 14nm FinFET | 28nm HKMG |
| Multi-core | Octa | Octa |
| CPU (Primary) | Cortex-A53 1.6GHz Octa | Cortex-A53 1.6GHz Octa |
| CPU (Secondary) | None | None |
| GPU | Mali-T830 MP1 | Mali-T720 MP2 |
| Video | Full HD 60fps encoding and decoding | Full HD 30fps encoding and decoding |
| Codec | HEVC (H.265), H.264, VP8 | H.264, VP8 |
| Display | WUXGA (1920×1200) | WUXGA (1920×1200) |
| Camera (Rear) | 16MP | 16MP |
| Camera (Front) | 16MP | 5MP |
| Camera (Dual) | 8MP+8MP | None |
| Modem | LTE Cat.6 2CA 300Mbps (DL) / 50Mbps (UL) | LTE Cat.6 2CA 300Mbps (DL) / 50Mbps (UL) |
| Connectivity | GNSS | None |
| Storage | eMMC 5.1, SD 3.0 | eMMC 5.1, SD 3.0 |
| Memory | LPDDR3 933MHz | LPDDR3 800MHz |
| Application | Smartphone, Tablet | Smartphone, Tablet |
