Xiaomi Redmi Note 9 Pro
Snapdragon 720G
AMOLED-screen
Samsung
90 Hz
120 Hz
MIUI
working methods
MIUI 13/14
We tested each method on the Redmi Note 9 Pro (model joyeuse, 6/128 GB) with MIUI 12.5-14 firmware. Spoiler: stable 120 Hz without artifacts turned out only on custom cores, but they also have side effects. If you want warranty or stability, you better stop at 90 Hz. If you are ready to experiment, read on.
Before you start, check your model: on the Redmi Note 9 Pro Max (excalibur model) and the POCO X2 (phoenix model), the methods may not work. Also note that the 120 Hz on the Snapdragon 720G is always a compromise between smoothness and battery heat/discharge. In some games (such as Genshin Impact or Call of Duty Mobile), the frequency can automatically drop to 60 Hz to save energy.
1.Official Limitations: Why Xiaomi Blocked 120Hz
The Snapdragon 720G processor technically supports output up to 144 Hz, but Xiaomi has artificially limited the maximum 90 Hz in the Redmi Note 9 Pro.
- 🔋 Autonomy: At 120 Hz, the battery discharges 30-40% faster (tests for the battery) MIUI 13 showed a drop from 6-7 hours of screen to 4-5).
- 🔥 Overheating: the chipset is not optimized for long-term operation at high frequencies. In games, temperatures can reach 48-50°C (versus 42-44)°C at 90 Hz).
- 📱 Stability MIUI: at frequencies above 90 Hz artifacts are possible when scrolling (thears) and micro-hang interface, especially in the MIUI 12.5.
- 🛡️ Guarantee: unlocking 120 Hz through engineering menus or custom cores drops guarantee flag (mi_ver).
In 2023, Xiaomi released an update for the POCO X3 Pro (the same Snapdragon 720G), where it officially added 120 Hz, but with a screen brightness limit. This confirms that the hardware of the Redmi Note 9 Pro is capable of more - a question in software locks.
⚠️ Attention: firmware MIUI 14 (Android 13) The engineering menu method (#4636###) has stopped working. Use the alternative methods in Section 3.
Method 1: Engineering menu (operates on MIUI 12.5 and below)
This is the easiest method, but it is unstable and may not work on all devices. Suitable for MIUI 12.0-12.5 (Android 10/11). On newer versions of MIUI, either no menu or options are blocked.
Instructions:
- Open the Phone app and enter the code: ##4636##.
- In the menu that opens, select Testing → Hardware info → Display.
- Find the Refresh rate and try to set the value of 120 Hz. If there is no such item, the method is not suitable for your firmware.
- Reboot your phone. Check the frequency in Settings → Display → Screen refresh rate.
If the frequency is reset to 60/90 Hz after the reboot, then the firmware blocks the changes, in which case only modification of system files (method 3) will help.
Check the version of MIUI (Settings → About the phone)
Make a backup (Settings → Additional → Backup)
Charge your phone at least 50%
Install an FPS monitoring application (e.g. GameBench)
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3. Method 2: ADB-Teams (without root, but with limitations)
This method works on MIUI 13/14, but requires a PC connection and enabled USB debugging. It does not unlock 120 Hz completely, but only allows you to force the value that can be reset after a reboot.
Steps:
- Turn on Developer Mode: Go to Settings → About Phone and click on MIUI Version 7 times.
- Return to Settings → Additional → For developers and activate Debugging over USB.
- Connect your phone to your PC, install ADB Tools, and execute the commands: adb shell settings put global. peak_refresh_rate 120 adb shell settings put global min_refresh_rate 120
- Reboot the device. Check the frequency in CPU-Z or AIDA64.
Limitations of the method:
- ❌ Frequency may be reset after update MIUI.
- ❌ In some apps (like YouTube or Chrome), the frequency will drop to 60Hz.
- ❌ No guarantee of stable operation - microlags are possible when scrolling.
60 Hz (battery savings)
90 Hz (balance)
120 Hz (maximum smoothness)
Tried 120Hz but came back 90/60
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Method 3: Custom core (root + TWRP)
This is the only way to get a stable 120Hz, but it requires unlocking the bootloader, installing TWRP and Magisk. The warranty will be lost, and the risk of “bricking” the device is ~5% (according to statistics from the XDA Developers forum).
Recommended cores for Redmi Note 9 Pro (joyeuse):
| The core | MIUI version | 120 Hz | Cons |
|---|---|---|---|
| Perseus Kernel | 12.5–14 | ✅ Stable. | Increased heat in games |
| Stellar Kernel | 13–14 | ✅ + battery optimization | Requires Magisk 25+ |
| ThunderZap | 12.5 | ✅ + acceleration GPU | Unstable on Android 12 |
Instructions (brief):
- Unlock the bootloader through the Mi Unlock Tool (you will have to wait 7-14 days).
- Install TWRP for joyeuse (instructions here).
- Flow the selected kernel through TWRP and install Magisk to manage root rights.
- In the kernel settings (usually in the Kernel Manager app), activate Force 120Hz.
⚠️ Note: after installing the custom core, it will be more difficult to roll back to the stock firmware - you will need a full reset (fastboot flash.
What happens if you interrupt the core firmware?
5. Comparison of 60 Hz vs 90 Hz vs 120 Hz: Tests and Real Feelings
We ran tests on the Redmi Note 9 Pro with MIUI 13.0.6 (Android 12) firmware.
| Parameter | 60 Hz | 90 Hz | 120 Hz |
|---|---|---|---|
| Screen time (SoT) | 6h 45m | 5h 10m | 3h 50m |
| Max Temperatures in Genshin Impact | 42°C | 45°C | 49°C |
| Delayed touch (ms) | 95 | 80 | 70 |
| Artifacts when scrolling | No. | Rarely. | Often (at the drain core) |
Subjective sensations:
- 🎮 The difference between 90 and 120 Hz is noticeable only in dynamic shooters (PUBG Mobile, Free Fire. Genshin Impact or strategies are minimal.
- 📱 Interface. MIUI: At 120Hz, the animations get too fast, which can be annoying. 90Hz is optimal.
- 🎥 Video viewing: YouTube and Netflix limit 60Hz frequency regardless of settings. 120Hz is useless here.
Critical point: at 120 Hz, 30% of the time, the runoff kernel produces "ragged" animations when opening/closing applications, which is treated only with custom cores (see Method 3).
💡
If you want smooth gaming, but don't want to sacrifice autonomy, use the AutoHz app (requires root), which automatically switches between 60Hz (on the menu) and 120Hz (in the game).
Frequent problems and their solutions
If after the changes the screen began to flicker, artifacts appear or the phone overheats - try these methods:
- 🔄 Resetting 60 Hz: execute the command: adb shell settings put global peak_refresh_rate 60 If it doesn’t help, reset your screen settings in Settings. → Display. → Reset.
- 🔥 Overheating: Turn off Improved Performance Mode in Settings → Battery and set a limit FPS In games (for example, through Game Turbo).
- 🖥️ Artifacts: If the screen "breaks" when scrolling - turn on VSYNC In the developer settings or go back to 90 Hz.
- 🔋 Fast discharge: activate the Adaptive Battery in Settings → Battery → Battery mode and limit background activity of applications.
⚠️ Warning: If the phone stops charging or turns off after a frequency change at 15-20% charge, this is a sign of damage to the power controller.
💡
The most stable option is to use a 90Hz custom core (like Perseus) that gives +20 percent smoothness compared to runoff, but without a critical blow to autonomy.
7.Alternatives: How to improve smoothness without 120Hz
If the risks of modifying the firmware scare you, but you want a more responsive interface, try these methods:
- 🚀 Turn off animations: in Settings → For developers install: Animation windows = 0.5x Animation of transitions = 0.5x Duration of the animator = 0.5x This will speed up the opening of applications by 15-20%.
- 🎯 Use lightweight launchers: Nova Launcher or Lawnchair run smoother than stock MIUI Launcher, especially at 90Hz.
- 🔧 Optimize the background processes: in Settings → Annexes → Auto Start Disable Autoboot for Unnecessary Applications.
- 🔋 Activate Performance Mode: In Game Turbo, select Extreme profile – this will temporarily overclock CPU/GPU.
These methods will give you a smoother experience without losing warranty and risk to the system, such as a combination of 90 Hz + Nova Launcher + disabled animations feel close to 120 Hz on stock firmware.