The flagship smartphone Xiaomi Mi 9, released in 2019, is still a topical choice for users who value the balance of performance and price. The main “heart” of this device was the Qualcomm Snapdragon 855 processor, the top solution of its time, which even 5 years later is not inferior to many modern mid-range chips. But what exactly is hidden under the hood of this smartphone? How 8-core architecture Kryo 485 and graphics accelerator Adreno 640 affect gaming capabilities and everyday work?
In this article, we will not only reveal the specifications of the Mi 9 processor, but also compare it with competitors (for example, with Huawei’s Kirin 980 and Samsung’s Exynos 9820), analyze the results of benchmarks like AnTuTu and Geekbench, and give practical tips on how to extend the life of the chipset in 2026. If you are planning to buy a used Mi 9 or just want to understand what its brain is capable of – read on!
Technical characteristics of the Xiaomi Mi 9 processor: Snapdragon 855 parsing
The Qualcomm Snapdragon 855 (SM8150) chipset was announced in December 2018 and was the company’s first 7nm processor built with TSMC N7 technology. This solution brought a significant performance boost over its predecessor, the Snapdragon 845, thanks to an optimized architecture and new cores.
The main components of the chipset:
- 🔹 Central processing unit (CPU): 8 Kryo cores 485 (1×2.84 GHz + 3×2.42 GHz + 4×1.80 GHz, based on architecture ARM Cortex-A76 and Cortex-A55.
- 🎮 Graphic accelerator (GPU): Adreno 640 with Vulkan 1.1 support, OpenGL ES 3.2. and hardware acceleration of ray tracing.
- 📡 Modem: Snapdragon X24 LTE (up to 2 Gbps per download, up to 316 Mbps per download).
- 🤖 Artificial Intelligence: 4th Generation AI Engine with a performance of up to 7 trillion operations per second.
- 📷 Image processing: Spectra 380 ISP (Support for up to 48 MP cameras and video recording 4K HDR).
Importantly, the Snapdragon 855 was Qualcomm’s first 5G chipset (via the X50 external modem), although the Mi 9 didn’t implement this feature, and the processor received an improved cooling system thanks to the vapor vapor-venting camera in the smartphone body, which reduces the risk of trottling under prolonged loads.
Comparison with competitors: Snapdragon 855 vs Kirin 980 vs Exynos 9820
In 2019, the Snapdragon 855 competed with two other flagship chipsets: the Huawei Kirin 980 and the Samsung Exynos 9820. All three processors were built on a 7-nm process, but had different approaches to architecture and optimization.
| Characteristics | Snapdragon 855 | Kirin 980 | Exynos 9820 |
|---|---|---|---|
| Technique | 7 nm (TSMC) | 7 nm (TSMC) | 8nm (Samsung) |
| CPU (max frequency) | 2.84 GHz (1 core) | 2.6 GHz (2 cores) | 2.7 GHz (2 cores) |
| GPU | Adreno 640 | Mali-G76 MP10 | Mali-G76 MP12 |
| AnTuTu (Grade Average) | ~370 000 | ~330 000 | ~350 000 |
| Support for 5G support | Yes (external modem) | No. | No. |
The Snapdragon 855 was ahead of the competition in most benchmarks, especially in graphics tasks thanks to the Adreno 640. However, the Kirin 980 demonstrated better energy efficiency, and the Exynos 9820 showed more stable performance in multithreaded loads. In real conditions, the difference between chipsets was minimal, but the Mi 9 stood out for better MIUI optimization for the Snapdragon.
⚠️ Note: When buying a used Xiaomi Mi 9, check the version of the processor in the settings (Settings) → The phone. → Some vendors are passing off models with a Snapdragon 845 (like the Mi 8) as Mi 9s, which is a scam!
Benchmark results: what is the Mi 9 capable of in 2026?
Despite its age, the Xiaomi Mi 9 still performs well in synthetic tests, and the following are the latest benchmarks for a smartphone with clean MIUI (no custom firmware) and 8GB of RAM:
- 📊 AnTuTu 10: ~350,000–380,000 (compared to Snapdragon 7 Gen 1 in 2026) ~500 000).
- 🧠 Geekbench 6: Single-Core: ~750-800 points; Multi-Core: ~2,400-2,600 points.
- 🎮 3DMark Wild Life: ~1,800–2,000 points (level) Mali-G77 In modern medium-budget smartphones).
- 🕹️ Game tests (FPS): PUBG Mobile (graphics) HDR + 60 FPS): ~55–60 FPS; Genshin Impact (Average Settings): ~30–40 FPS; Call of Duty: Mobile (Maximum Graphics): ~50–55 FPS.
As you can see, the Mi 9 still pulls modern games on medium settings, but in heavy projects like Genshin Impact or Honkai: Star Rail you will have to sacrifice graphics for a stable FPS. For everyday tasks (social networks, video, multi-tasking), performance is enough with a margin.
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To improve performance in games, turn off background processes through Settings → Apps → Autostart and activate Performance Mode in Settings → Battery → Power Modes
Trottling and overheating: how to avoid falling productivity
One of the weaknesses of the Snapdragon 855 in the Mi 9 is its tendency to trottling, which is a forced frequency reduction when overheated, especially in games or when recording video in 4K for long periods.
- 🔥 Compact smartphone case (6.39) with limited cooling space.
- 📉 Not always effective operation of the ventilation hole (clogged with dust over time).
- 🔋 Wear of thermopaste (after 3-4 years of operation).
To minimize trolling, follow these recommendations:
Remove your case during games
Use a cooling stand
Update MIUI to the latest version
Clean the dust charger connector
Replace the heat paste (when disassembling)-->
If your smartphone is too hot even in simple tasks, check:
- Battery state (the worn-out battery loads the processor).
- The presence of viruses or background mining applications.
- Integrity of the heat conductive gasket (requires disassembly).
⚠️ Warning: If the Mi 9 suddenly turns off when heated to 60°C+, This could indicate a power controller malfunction, which requires a diagnosis at the service center.
Performance Optimization: Tips for Extending the Life of a Chipset
Even after 5 years, the Snapdragon 855 can be overclocked software if you configure your smartphone correctly.
1. MIUI settings for maximum performance
Go to:
Settings → About Phone → MIUI version (shap 7 times to turn on the developer mode)
Settings → Additional → Developers → Restricting background processes (select “No Limits”)Also turn off the interface animation:
For developers → Scale of window animation (0.5x)
For developers → Transition animation scale (0.5x)2. Use of custom cores (for advanced)
If you have a bootloader unlocked, you can install a FrancoKernel or Kiriski kernel that is optimized for the Snapdragon 855.
- 🔋 Energy management;
- 🎮 Stability FPS play;
- 📡 Communication quality (fixes for modems).
⚠️ Warning: Installing custom cores requires unlocking the bootloader and can lead to loss of warranty (if it is still valid.
What's a bootloop?
3.Cache cleaning and defragmentation
Over time, the system becomes clogged with temporary files, which slows down the processor.
Settings → Memory → Cleaning (use the built-in tool)
Settings → Applications → Select the application → Storage → Clear the cache💡
Regularly cleaning the cache and disabling auto-run of unnecessary applications can increase performance by 15-20% without an iron upgrade.