ZTE Nubia Z9 Max (NX512J) Firmware Flash File Download [Stock Rom]
The Nubia Z9 Max (model NX512J) is a premium flagship smartphone from 2015, featuring the powerful (and notoriously hot) Snapdragon 810 chipset and a premium metal frame. This page provides official OTA (Over-The-Air) update packages for the device. For owners of this classic flagship, manually installing a software update can help resolve persistent bugs, improve system stability, and address performance throttling issues.
Important Note: This is an OTA update package, not a full firmware for unbricking a dead phone. It must be installed on a functioning device. Your phone must also be on 100% stock, un-rooted firmware with the original recovery for the update to install successfully.
Quick Device Specs
- Device
- Nubia Z9 Max (NX512J)
- Release year
- 2015
- Chipset
- Qualcomm Snapdragon 810
- Display
- 5.5″ FHD IPS LCD (1920×1080)
- Battery
- 2900 mAh (Non-removable)
- Memory
- 3GB RAM + 16GB storage
- Camera
- 16MP rear, 8MP front
- OS
- Android 5.0.2 (Lollipop)
- Special Feature
- Titanium alloy frame
Required Downloads
You only need the OTA update file itself to perform this installation. No PC or special tools are required.
Stock ROM & Firmware
Two different builds are available. If one fails to install on your device, please try the other.
| Version / Build Date | Android | Region | Type | Download | Size |
|---|---|---|---|---|---|
| V4.07 | 5.0.2 (Lollipop) | Global/China | OTA | Download | ~900 MB |
| (2015-09-06) | 5.0.2 (Lollipop) | Global/China | OTA | Download | ~900 MB |
Quick Installation Guide
There are two methods to install an OTA update package.
- Via Settings Menu: Download the `.zip` file and move it to the main (root) directory of your internal storage. Go to `Settings` > `System` > `System Update`, tap the menu icon in the corner, select `Local update`, and choose the file.
- Via Stock Recovery: Download the `.zip` file and move it to your internal storage or SD card. Power off the phone, then boot into recovery mode (hold Volume Up + Power). Select `Apply update from…` and choose the `.zip` file.
For a complete, step-by-step tutorial with screenshots for both methods, please refer to our definitive guide:
How to Manually Install Official OTA Updates on Android
FAQs
Q1. My Nubia Z9 Max overheats constantly. Will this update fix it?
The Snapdragon 810 chipset is famous for running very hot. While this OTA update includes software optimizations that can help manage temperature and performance, it cannot change the fundamental nature of the hardware. The phone will still get warm under heavy use. A clean install can help by removing rogue processes.
Q2. Is this firmware for the Nubia Z9 or Z9 Mini?
No. This firmware is strictly for the large-screen Z9 Max (NX512J). The standard Z9 (with its borderless screen) and the Z9 Mini are different devices with different hardware. Using the wrong firmware will brick your phone.
Q3. Why are my notifications delayed?
This is a common issue with Nubia UI’s aggressive battery management. This update may improve it, but you will likely need to go to `Settings > Power management` and manually exclude important apps like WhatsApp from battery optimization to receive notifications instantly.
Device-Specific Troubleshooting
- Performance Throttling (Slowing Down When Hot): This is a built-in safety feature to prevent the Snapdragon 810 from overheating. A firmware update ensures this system is working as intended. If your phone becomes very slow during use, it is a sign it’s throttling due to heat and you should let it cool down.
- Poor Battery Life: A clean OTA install can resolve software bugs causing abnormal battery drain. To get the most from the 2900 mAh battery, reduce screen brightness and use the power management settings to control which apps can run in the background. The overheating chip is a primary cause of battery drain.
- “Verification Failed” During Installation: This error means your system has been modified (rooted, custom recovery) or you are on a custom software version. This official OTA will only install on a 100% stock, un-rooted device. You must flash a full QFIL firmware first to restore the phone to its original state.
- Device is stuck in a bootloop after update: If the update causes a bootloop, the best option is to boot into recovery (Volume Up + Power) and perform a `Wipe data/factory reset`. Note that this will erase all your personal data.
