Xiaomi Redmi Note 9S, based on the Snapdragon 720G processor, was originally positioned as a strong middle peasant capable of pulling popular games on average settings. However, over time, the optimization of the MIUI system can deteriorate and the requirements of applications grow, which forces users to look for ways to overclock the device. Overclocking in the context of modern Android smartphones often means not only increasing the clock speed of the processor, but also comprehensive optimization of the system, unlocking the bootloader and installing specialized software.
Before taking action, you need to understand the risks: any interference with the software that goes beyond the standard user settings can lead to a loss of warranty or, in the worst case, to the device becoming a brick. Unlocking the bootloader is the first and mandatory step for deep modification, but it is this that often causes difficulties for beginners.
In this article, we will discuss in detail all the steps to speed up your gadget: from safe methods of cleaning the system to advanced manipulation of the kernel and recovery. You will learn how to properly prepare the Redmi Note 9S for modifications, what tools you will need and how to avoid critical errors. Remember that overclocking on the Snapdragon 720G is possible only through custom cores, since this function is blocked by standard MIUI tools.
Device preparation and data backup
The Xiaomi Redmi Note 9S acceleration process should start with careful preparation. Standard procedure requires freeing up space on the internal drive and creating a full copy of important data. Even if you plan only superficial optimization, the risk of file loss in case of failures is always there, so you should not neglect the backup.
You will need a computer with Windows operating system, which is good. USB-cable (preferably original or certified) and stable Internet connection. ADB And Fastboot, which is the bridge between the PC and the smartphone in debugging mode. Without these components, no commands can be executed.
Use the built-in MIUI or third-party backup. Go to Settings → About Phone → Backup and Restore. Select all important sections: contacts, messages, call log and application data. Once completed, copy the backup file you created to your computer or to cloud storage.
⚠️ Warning: Before any manipulations, make sure that the battery is at least 60% charged. Interrupting the firmware or unlock process due to battery discharge can lead to irreversible damage to the software part.
The next step is to activate the developer mode. Go to Settings. → About the phone and quickly press 7 times on the item "Version" MIUI». After the message “You became a developer” appears, go to the menu Additional → For developers, you need to activate the "Debugging by" items. USB» and “Facilities release».
Unlocking the bootloader (Bootloader Unlock)
Unlocking the bootloader is a fundamental step without which installing a custom TWRP recavator or obtaining the rights of a Root superuser is impossible. Xiaomi artificially limits this possibility by requiring waiting for 168 hours (7 days) after the account is linked, a security measure that cannot be circumvented by official methods.
To start the process, you will need the Mi Unlock Tool, downloaded from the official website. After installing the program and logging into your Mi Account, link the device to the account through the phone's settings menu (Developers → Mi Unlock Status).
The unlocking process is as follows:
- 🔌 Connect the off smartphone to the PC, clamping the volume buttons “Down” and “Power” to enter Fastboot mode at the same time.
- 🖥️ Run Mi Unlock Tool on your computer and wait for device definition.
- 🔓 Press the Unlock button and confirm the action. If less than 7 days have passed, the tool will tell you to wait.
- 🔄 After successful unlocking, the phone will automatically restart and reset all data to the factory.
It is important to understand that unlocking the bootloader makes the device vulnerable from a data security perspective, as an attacker with physical access will be able to access the file system.In addition, some banking applications and services (for example, Google Pay in some configurations) can stop working without additional manipulations to hide root rights.
Once unlocked, the "open lock" icon will appear on the boot screen, which is normal behavior for modified Xiaomi devices. The path to installing more productive components is now open.
Installation of custom TWRP Recovery
Xiaomi’s regular recovery menu is extremely limited in functionality and doesn’t allow you to install third-party firmware or make full system backups. It’s replaced by TWRP (Team Win Recovery Project), the gold standard for custom recoveries. For the Redmi Note 9S (codename curtana), you need to look for a stable build that is compatible with your version of Android.
Installation is done via Fastboot mode using the command line. First, upload the image file twrp.img to the folder with the ADB tools. Then transfer the smartphone to Fastboot mode and connect to the PC. In the command line, execute the command:
fastboot flash recovery twrp.imgIf you just release the buttons and the phone boots into the system, the regular one is MIUI re-write TWRP So you need to log in to the recovery menu immediately after you've been firmware. TWRP First, make a full backup of the Boot, System and Data partitions on the SD-map USB-accumulator.
☑️ Pre-installing check TWRP
Interface. TWRP allows you to perform complex operations: partition cleaning (Wipe), installation ZIP-It's the basic tool for any modder. TWRP Gives you full control of the device’s file system.
Getting Root rights and installing Magisk
For deep optimization and overclocking, the Xiaomi Redmi Note 9S requires superuser rights. The current standard is Magisk. It allows root access in a systemless way, which means modifying the boot partition without changing the system partition, making it easier to hide rights from banking applications.
Magisk installation process for Redmi Note 9S involves patching the boot image. You will need the original file boot.img It's from the firmware that's now on the phone. FASTBOOT-Firmware (archive.tgz) or pull out using ADB, If you have a root on a temporary Recovery, the algorithm is as follows:
- Copy the boot.img file into your smartphone memory.
- Install the Magisk app (APK) and open it.
- Click “Install” next to Magisk and select “Select and Patch File”.
- Specify the path to boot.img. Magisk will create a patched file in the Download folder.
- Remove the received file (usually) magisk_patched_xxxx.img) computer.
- The following is a quickboot flash boot. magisk_patched_xxxx.img
Once rebooted, the Magisk icon will appear in the App Manager, and the settings menu will display superuser status. Now you can install modules that directly affect processor performance and memory.
⚠️ Note: When installing modules that change system files, always have the ability to restore the original image at hand. boot.img via Fastboot, otherwise the device may go into a cyclic reboot (bootloop).
With Root rights, applications are available to fine-tune cores, manage power consumption and force the closure of system services that eat up resources.
Methods of real overclocking of the processor and GPU
Now, to the heart of the matter, how do you really squeeze more FPS out of the Snapdragon 720G. With standard MIUI, you can't do that because the frequencies are hard-coded in the kernel. However, with Root rights and KSU installed or specialized applications (like Kernel Adiutor or FRK Kernel Manager), you can change the CPU and GPU settings.
Overclocking involves increasing the maximum core clock speed. For the Snapdragon 720G, you can try to raise the standard values, but this carries risks of overheating. A safer and more efficient method is Undervoltage, combined with unlocking all cores. Often manufacturers underestimate the frequencies for stability on all chip instances, so your processor can work stably at higher frequencies.
Control of thermopast and cooling is also important. When you accelerate actively, the body temperature will rise. Use real-time temperature monitoring apps. If the temperature is above 45-50 degrees under load, the system will start to reset frequencies (tottl), and you will not notice any increase in performance.
Comparison of optimization methods is presented in the table below:
| Method | Security | FPS growth | Difficulty |
|---|---|---|---|
| Memory Clearance (RAM) | Tall. | Low (5-10%) | Low. |
| Shutdown of animations | Tall. | Medium (visually) | Low. |
| Overclocking the GPU (Adreno) | Medium | High (15-25%) | Tall. |
| Castomic nucleus | Low. | Maximum | Very high. |
One effective way is to use Magisk modules such as Universal GDoS or Cooler optimization scripts, which change the algorithms of the task scheduler, forcing the system to aggressively keep high frequencies in games.
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Use an external cooler for your smartphone during overclocking tests, which will determine whether performance is limited by thermal throttling, rather than program limits.
Optimizing MIUI and removing system debris
Even without hardware overclocking, software optimization can do wonders. MIUI is famous for its heavy weight and many background processes. The first step is to turn off unnecessary services. Go to Settings → Apps → All applications and find system services that can be safely stopped, such as Mi Video, Mi Music, Analyticas, MSA (advertising service).
To remove system debris and bloatware (preinstalled applications) with Root rights, you can use the System App Remover app. Be careful: removing critical system components (such as Security or bootloader) will cause your phone to fail. Only remove what you are sure of, or use ready-made safe removal lists for your model.
It's also recommended to scale down animations. In the developer menu, find "Scale of window animation," "Scale of transition animations," and "Duration of animations." Set 0.5x or turn off animation altogether, which creates the illusion of faster interface performance.