How to increase the performance of Xiaomi Redmi Note 9: from basic settings to deep optimization

Why Redmi Note 9 is starting to brake and how to fix it

Xiaomi Redmi Note 9, based on the MediaTek Helio G85 processor and 3-6 GB of RAM, was originally positioned as a powerful device for gaming and multi-tasking. However, over time, even it begins to slow down: applications open for a long time, animation twitches, and in games there are friezes, the reasons for this behavior lie not only in the “aging” of iron, but also in the features of the MIUI firmware, which actively consumes resources in the background.

The main culprits of the performance drop: 1) Clogged memory – app cache, junk files and duplicates occupy up to 30% of internal storage. 2) Autoboot – MIUI defaults to run up to 20 services when you turn on your phone, even if you do not use them. 3) Thermal trottling – when overheated above 45 ° C, the processor automatically reduces the frequency, which leads to lags. 4) Outdated firmware – new versions of MIUI 14+ optimized memory management algorithms, but many users do not update for years.

In this article, we will discuss the unique optimization methods for the Redmi Note 9, which are not applicable to other Xiaomi models due to the features of its hardware platform (for example, support for HyperEngine technology in the Helio G85).

1. Cleaning the system: remove garbage and free up memory

The first step is to free up space on the internal drive. The Redmi Note 9 has 64/128GB of storage, but even that doesn't last long if you don't keep track of the files.

• 🧹 Cache Clearing: Go to Settings → Annexes → App management, select any app (e.g. Facebook) and click "Clear Cache." Repeat for top-10 The most "heavy" applications in memory.
• 🗑️ Removing Duplicates: Use the Built-in Security App → Cleanup → Duplicate files. Especially a lot of duplicates are stored in the folder. DCIM/Camera (burst-shot).
• 📁 File Transfer: Move photos and videos to MicroSD (if any) or to the cloud".
• 🚫 Disabling unnecessary applications: C Settings → Find the pre-installed services (Mi Video)>, Mi Music) and hit "Disable." It won't delete them completely, but it will stop background activity.

For deep cleaning, use third-party utilities: SD Maid (the paid version) finds residual files after uninstalling apps, and Files by Google is a free tool to find large and unnecessary files. Careful: do not delete Android folders, MIUI or files with the.obb extension - these are game data and system files.

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If your phone is slowing down when you open a gallery, try renaming your folder. DCIM/.thumbnails into.thumbnails_bak The system will create a new thumbnail folder, and the old one will remain as a backup.

⚠️ Note: Do not use cleaners like Clean Master or CCleaner, which often delete important files. MIUI, This leads to camera or sensor failures. Xiaomi's official Security app is safer.

2. MIUI optimization: disabling background processes and animations

MIUI is known for its heavyweight features, due to its many background services, to reduce the load:

• 🔄 Turn off Autostart: Go to Settings → Annexes → Application management → Autostart and deactivate autoboot for all applications except system (Phone, Messages).
• 📱 Limit background activity: In the same menu, select Permissions → Background activity and set the "Limited" mode for most applications".
• ⚡ Speed up animation: Activate Developer Mode (7 times tap on Settings) → The phone. → Version. MIUI), then in Settings → Additionally. → For developers, set: The scale of the window animation = 0.5x, Scale of transition animation = 0.5x, Duration of the animator = 0.5x.
• 🌙 Turn on dark theme: It reduces the processor load when rendering the interface. Activated in Settings → Screen. → Dark subject matter.

For advanced users: in Settings → Battery and Performance → Performance mode, select Balance over Battery Savings. This will disable CPU clock limits, but reduce battery life by 10-15%.

Turn off autoplay for 10+ apps | Size animation 0.5x| Switch to dark theme | Select Balance performance mode | Clear the cache in Security app-->

3. RAM Management: How to Free RAM

Redmi Note 9 comes with 3/4/6 GB of RAM, but is really available to the user 1-1.5 GB less due to background MIUI processes.

• 🔍 Monitoring of use: Install AIDA64 (Free version) and check which apps consume the most RAM.Frequent culprits: Facebook (up to 500 MB), Instagram (300-400 MB), MIUI Daemon (system process, up to 200 MB).
• 🚪 Compulsory Closing: In Settings → Select the "sweeten" app and click "Stop." For convenience, add the "Memory Cleanup" widget to the home screen.
• 🔄 Reboot on schedule: In Settings → Additionally. → Reboot set up automatic phone reboot once a day (e.g. at 3:00) This clears RAM without losing data.
• 📱 Use Lite versions: Replace heavy apps with lightweight ones: Facebook Lite instead of Facebook, Messenger Lite instead of Messenger, Twitter Lite (PWA-browser-based).

For manual memory management, activate Settings → Additional → For developers, the option to Do Not Stay Activated. This will cause applications to close immediately after folding, but free up to 30% of RAM. Not recommended for multi-tasking.

⚠️ Note: Do not use applications like this RAM Booster or Game Booster from third-party developers, they forcibly kill processes, which leads to a reboot of system services and increases battery consumption. MIUI Memory Optimizer Works More Efficiently.

4. Optimization for gaming: GPU overclocking and cooling

The Redmi Note 9 with the Helio G85 processor supports HyperEngine technology, which dynamically allocates resources between the CPU and the GPU. To maximize this potential:

• 🎮 Enable the game mode: In Settings → Special facilities → Play mode activate the option and add your games to the list. This will turn off notifications and optimize performance.
• ❄️ Control the temperature: Set the CPU Monitor and ensure that the temperature does not exceed 42°C. At 45.°C+ And the trottling goes off, and FPS fall 30-50%.
• 🔧 Set up the graphics in games: In PUBG Mobile select "Balanced" and "High" framerate. In Genshin Impact, lower the resolution to 720p and turn off the shadows.
• 🔋 Use charging while playing: At a charge below 20%, the processor automatically limits performance. Connect charging (preferably original to the original one) 18W), But remove the cover for better cooling.

For advanced users, with the Game Turbo app (preinstalled in MIUI), you can manually adjust the clock speed of the GPU. Go to Game Turbo → Settings → Performance and select the Extreme profile. This will increase FPS by 10-20%, but reduce battery life.

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Use a cooling stand with a fan for games lasting >30 minutes, which prevents trottling and improves FPS stability by 15-25%.

5. Updating the firmware and core: official and custom solutions

Official MIUI updates often include model-specific optimizations. For the Redmi Note 9, the current versions are: MIUI 14 (Android 12) - the latest stable firmware with patches for the Helio G85. MIUI 15 (Android 13) - beta, available through the MIUI Beta Tester program.

To update:

1. Go to Settings → About the phone → System update.
2. Click on the three dots in the upper right corner and select "Select Service Pack" if you downloaded the firmware manually (the file should be called update.zip and lie at the root of the memory).
3. Connect your phone to charging and wait until it is completed (don’t interrupt the process!).

For enthusiasts: custom firmware like LineageOS 20 or Pixel Experience can give a performance boost of up to 30%, but require unlocking the bootloader and installing through TWRP. Risks: loss of warranty, possible bugs with the camera or sensors.

⚠️ Note: When updating via fastboot (for example, when changing the firmware region), use only official ones. ROM Firmware from third-party sites (e.g. xiaomifirmware.com) may contain modified boot samples, resulting in a brick (complete inoperability) device.

Hardware methods: replacement of thermopastes and batteries

If software methods did not help, the problem may be in the "iron". After 2-3 years of operation: 1) The thermopast between the processor and the radiator dries up, which leads to overheating and trottling. 2) The battery loses capacity, and at a discharge below 30%, the processor artificially limits performance.

To replace the thermal paste:

1. Take the phone apart (you need a plastic transmitter and a T3 screwdriver).
2. Remove the metal plate from the processor and clean the old paste with alcohol.
3. Apply the new thermopaste (recommended by Arctic MX-4 or Thermal Grizzly Kryonaut) with a thin layer.
4. Collect your phone and check the temperature in AIDA64 under load.

Signs of a worn-out battery:

The phone turns off at 20-30% charge.

Fast discharge (from 100% to 0% in 3-4 hours with an average load).

Bloating (check if the phone is on the table).

Replace the battery with the original (BM47 for the Redmi Note 9) or the quality analog (Green Cell, Baseus).

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After you change the battery, recalibrate it: fully charge the phone, then discharge it until it turns off automatically. Repeat the cycle 2-3 times. This will restore an accurate display of the charge level.

7.Reset to factory settings: Last chance

If all methods have been tried, but the phone is still braking, do a hard reset, which will delete all data, but return the device to a "clean" state.

1. Back up via Settings → About Phone → Backup or Mi Cloud.
2. Go to Settings → About Phone → Resetting → Erase all data.
3. Enter the password and confirm the reset. The phone will restart and start the process (it will take 5-10 minutes).
4. Once turned on, set up the phone as new without restoring data from a backup (this could bring back old issues).

Alternative method (if the phone is not turned on):

1. Turn off the device.
2. Press Volume Up + Power before the Mi logo appears.
3. From the recovery menu, select Wipe Data → Wipe All Data (manage volume and power buttons).

⚠️ Warning: Don't install all apps at once after resetting. Add them one at a time for 2-3 days to monitor performance. Often, brakes are caused by a conflict of specific applications (e.g. Facebook). + VK + TikTok at the same time).

FAQ: Frequent questions about Redmi Note optimization 9