How to speed up Xiaomi Redmi 9T: a complete optimization guide

Xiaomi Redmi 9T is one of the most popular budget smartphones with a balance of price and performance, but over time even it begins to “slow down”. The reasons can be different: overloaded memory, background processes, outdated firmware or battery wear. In this article, we will discuss all working methods of acceleration, from basic to advanced, taking into account the features of MIUI and the Snapdragon 662 hardware platform.

It's important to understand that there's no magic button that will instantly return a smartphone to factory speed, but a comprehensive approach -- cleaning up the system, optimizing settings, and hardware tricks -- can yield results. +40% performance (AnTuTu tests on identical devices) Start with simple methods and gradually move to deeper settings.

1.Diagnosis: Why is the Redmi 9T slowing down?

Before optimizing, you need to identify bottlenecks.The Redmi 9T can slow down for the following reasons:

• 📱 Overloaded memory: Less than 10% of the free space on the internal drive leads to lags due to fragmentation of data.
• 🔄 Background processes: MIUI aggressively caches applications even when they are not in use.
• 🔋 Worn-out battery: With a capacity below 70% of the nominal value, the processor automatically limits performance.
• 📲 Older versions: in older versions MIUI (below 13.0) there are bugs with control of RAM.
• 🦠 Viruses or malware: especially if installed APK unverified.

To accurately identify the problem, follow the following steps:

1. Check the free space: go to Settings → About phone → Memory.
2. Run Security → Scan to search for viruses.
3. Install the AccuBattery app (from Google Play) to analyze the battery status.
4. View active processes in Settings → Applications → Launched.

Critical indicators for which intervention is required:

⚠️ Note: If AccuBattery shows that the battery is lower 60%, So, software optimization won't work, it requires a battery replacement. 50-70% The smartphone will slow down even after resetting the settings.

2. Memory cleanup: remove garbage and cache

The most common cause of lag is clogged memory. The Redmi 9T has 64 or 128 GB of internal memory, but even that doesn't last long if you don't keep track of the files.

• 🧹 Delete unnecessary files: Open files → Categories → Large files and remove the video/photo weight >100 MB. Check the Download folders and DCIM/.thumbnails — There's a lot of duplicates.
• 🗑️ Clear the app cache: Go to Settings → Annexes → App management. Select the heaviest app (like Facebook or TikTok) → Warehouse → Clear the cache.
• 📁 Transfer files to memory card: In Settings → Memory. → By default, select Memory Map. Use Files by Google to automatically transfer photos/video.

For deep cleaning, use the built-in MIUI tool:

1. Open Security. → Cleanup.
2. Press Deep Clean and wait for analysis.
3. Delete all items except Call Logs and Messages (if they are important).
4. Reboot your smartphone.

Hidden folders that can be safely cleaned (only if you don't use root access!):

/storage/emulated/0/Android/data/*/cache


/storage/emulated/0/Android/obb/ (delete the files of games you don't use)




/storage/emulated/0/DCIM/.thumbnails

⚠️ Note: Do not delete Android folders or MIUI It will cause a system failure, and don't touch files with the.odex or.vdex extension.

3. MIUI Optimization: Turning off animation and background processes

MIUI is not just a shell, it's a whole range of services that can slow down the system. Even if you have a clean Redmi 9T without viruses, some functions run in the background and consume resources.

• 🎭 Interface animation: Activate Developer Mode (7 times click on Version) MIUI In Settings → About the phone. Go to Settings. → Additionally. → For developers, find the items Window animation scale, transition animation scale and animator duration — set the value off. or 0.5x.

Another hidden resource eater is Xiaomi services, which can be partially disabled:

1. Go to Settings → Notifications → Notifications Management.
2. Find system applications like Mi Video, Mi Music, GetApps.
3. Turn off notifications and background activity for them.

💡

If the interface seems too sharp after disabling the animation, set a 0.5x value instead of completely turning it off. This will keep the interface smooth, but speed up the transitions between the screens.

For advanced users, there is a way to disable ads in MIUI, which also slows down the system:

adb shell pm disable-user --user 0 com.miui.systemAdSolution

This command must be executed via ADB (instruction below in the section about firmware).

4.RAM Control: How to Free RAM

The Redmi 9T has 4GB of RAM, but MIUI doesn't always manage it efficiently. If there's 30+ processes in the Task Manager, here's how to fix it:

• 🚀 Forced RAM Release: Hold the Home button (or swipe up and hold in) MIUI 12+). Click on the Close Everything icon (cross or trash can) in some versions. MIUI There is a button Clean in the upper right corner.

Myths about RAM, which you should not believe:

• ❌ «The more free RAM, the better» → Actually. MIUI caches frequently used applications for quick launch.
• ❌ «Task killer speeds up phone» → Forced shutdown of processes can lead to frequent restarts, which will only increase the load.
• ❌ «4GB of RAM is not enough for modern games» → Redmi 9T Snapdragon 662 is optimized for Call of Duty Mobile and PUBG mid-set.

If after all the manipulations, RAM is still overloaded, try rolling back updates for problematic applications:

1. Open Settings → Applications → Application Management.
2. Select an app (like Facebook) → Three dots → Remove updates.
3. This will bring the program back to the factory version, which often works more stable.

5. Update firmware and reset settings

If the Redmi 9T is slowing down on the older version of MIUI, the first thing to do is update the firmware. Xiaomi regularly releases patches that fix memory and performance management bugs. Here's how to update correctly:

• 🔄 Through Settings: Go to Settings → The phone. → Update system. Click Check Updates. If a new version is available, download and install it (preferably via Wi-Fi).

Manual installation (if OTA does not work)

1. Download the latest firmware for Redmi 9T (codename lime) from en.miui.com.
2. Put the update.zip file in the root of the phone’s memory.
3. In System Update, click on three points → Select a firmware file.

Important nuances when updating:

• 🔋 The battery should be charged. >50%.
• 📶 Use a stable Wi-Fi connection (not mobile internet!).
• 🔒 Do not interrupt the process – this can lead to a brick (breakdown) of the phone.

⚠️ Attention: After the Redmi reset 9T first 1-2 It's okay to work slower than usual, and it takes time for the system to optimize the background to suit your habits.

Even if the reset didn’t help, it could be the corrupted system files, in which case only the Fastboot flashing (instructions in the next section) will help.

6 Advanced methods: overclocking, firmware and root

If the standard methods have failed, you can try advanced methods, but they require experience and may not warranty.

• 🚀 Overclocking the processor (requires root): Install Kernel Adiutor or FrancoKernel from Google Play. CPU Increase the maximum core frequency to 2.0 GHz (standard for Snapdragon 662). Do not exceed 2.1 GHz - this can lead to overheating!
• 📲 Install custom firmware: Popular firmware for Redmi 9T: LineageOS 18.1, Pixel Experience, HaventOS. You need an unlocked bootloader to install and TWRP. Instructions: Unlock the bootloader through the Mi Unlock Tool. Install TWRP Fastboot: Fastboot Flash Recovery twrp.img fastboot boot twrp.img V TWRP make a Wipe → Advanced Wipe (select Dalvik, Cache, Data, System). ZIP Firmware and GApps (if you need Google services).

Getting root rights

• Download Magisk from the official website.
• In TWRP, go Magisk.zip.
• After the reboot, install Magisk Manager to manage modules.

Risks of advanced methods:

• ❌ Loss of warranty (if you do not return the stock firmware before contacting the service).
• ❌ The possibility of brick (turning the phone into a “brick”) in case of firmware error.
• ❌ Problems with Google Pay, Netflix and banking apps (due to SafetyNet).

If you decide on a custom firmware, here are the recommendations for choosing:

⚠️ Warning: Before firmware, check the phone model with the command fastboot getvar product. 9T (codename lime) only fits firmware marked lime! Install firmware for Redmi 9 or Note 9T will cause the device to fail.

Hardware methods: battery and thermal paste replacement

If the software didn't work, the problem could be the hardware, two of the most common "iron" brake factors:

• 🔋 Worn-out battery: With capacity below 70% Power controller limits processor performance. check battery health in AccuBattery or through code ##4636## (Battery information section: Cost of battery replacement at service center: ~1500-2500 ₽ (original).
• 🌡️ CPU overheating: Snapdragon 662 is prone to trottling (automatic frequency reduction) at temperature >60°C. Causes of overheating: high load, dried thermal paste, dust in the case. Solution: replacement of the thermopaste (cost in service: ~1000 ₽) Or self-cleaning (requires disassembly of the phone). How to check the temperature of the processor: Set up CPU Monitor AIDA64. Run a performance test (e.g. AnTuTu) if the temperature is above 70°C is critical. If you're going to replace the thermopaste yourself, you're going to need: A set of screwdrivers. T3-T5 For Xiaomi, Arctic Thermopaste MX-4 or KPT-8. Plastic blade for the accurate opening of the case. ISO pyro. 💡Before disassembling the phone, take a picture of the location of all the plumes and screws. 9T There are 3 types of screws: under the cross screwdriver, under the Torx T3 under the Y-type. Don't confuse them when you build! Signs it's time to change the battery: The phone is running out of power 3-4 The percentage of charge "jumps" (for example, from a moderate use) 30% straight away 10%). The device is switched off when 15-20% Bloating of the body (see above the rear cover raised). ⚠️ Warning: If the battery is swelling, you can't try to prick it or heat it up! This can cause fire. 8. Alternative solutions: cloud games and lightweight firmware If Redmi 9T It's not like modern games or apps, it's not necessary to change them: ☁️ Cloud Gaming: Services like Xbox Cloud Gaming, GeForce NOW Or Booid, you can play heavy games on a weak phone. >20 Mbit / s and gamepad (you can connect via Bluetooth). Pros: not loading the phone, always current versions of games. Cons: possible lags with poor connection. 📱 Lightweight firmware: Android Go-based firmware (like LightROM) is optimized for weak devices, stripped down functionality but fast, suitable for older people or as a spare phone. 🔄 Using your phone as a workstation: Connect Redmi 9T monitor USB-C to HDMI Adapter. Use DeX modes (via Second Screen in the MIUI) For performance, connect your keyboard and mouse over Bluetooth. Cloud services for games comparison: Service Cost Internet requirements Supported Xbox Cloud Gaming Games Included in Xbox Game Pass (from 300) ₽/10 months+ Mbit/s Forza Horizon 5, Halo Infinite, Starfield GeForce NOW Free (1 hour session) or 1000 ₽/month 25+ Mbit/s Cyberpunk 2077, GTA V, Fortnite Booid Free (with ads) 15+ Mbit/s PUBG Mobile, Call of Duty Mobile, Free Fire If you choose lightweight firmware, pay attention to: LightROM - based on the MIUI, DerpFest is a custom firmware with a focus on performance. Posp is a minimalist Android.