Key Features at a Glance
All-Big-Core CPU design (all cores are “big” performance cores).
Premium graphics engine, with a focus on reducing power usage and increasing efficiency/performance.
Generative AI support: latest NPU, agentic AI engine, NeuroPilot toolkit, mixed-precision etc.
Strong imaging and video capabilities (HDR, camera zoom, video recording)
Up-to-date connectivity: 5G Advanced modem, Wi-Fi 6E, etc.
Detailed Specifications
Component Specification
CPU
Octa-core, All Big Core design
• 1× Arm Cortex-A725 (1 MB L2)
• 3× A725 (512 KB L2 each)
• 4× A725 (256 KB L2 each)
• Shared caches: 6 MB L3, 5 MB SLC (“System Level Cache”)
Memory & Storage Memory type:
•LPDDR5X; maximum frequency ~ 8533 Mbps. •Storage type: UFS 4 + MCQ (multi-channel queue)
GPU / Graphics Arm Mali-G720 MC7;
• includes MediaTek Frame Rate Converter (MFRC).
•Improvements: ~24% higher peak GPU •performance; −42% power use for graphics.
AI / NPU MediaTek NPU 880;
• Generative AI capable.
• Features including: agentic AI engine (DAE), mixed precision (INT4 quant), NeuroPilot toolkit, acceleration in certain models (e.g. Baichuan 4B text generation, Stable Diffusion v1.5)
Camera
• Imaging Supports up to 320 MP camera sensors; also 3× 32 MP at 30 fps.
•Max video capture: 4K @ 60 fps.
•Additional imaging features: QPD remosaic tech for better light capture, in-sensor zoom with 100% PDAF, full HDR video across zoom range.
Display Supports up to WQHD+ resolution displays at up to 144 Hz refresh rate. Dual screen support also noted.
Connectivity:
•5G Advanced modem: supports Sub-6 GHz FR1
• 5G-CA (carrier aggregation),
• 4G-CA, 5G FDD/TDD, etc.
• Downlink: up to 3-component carrier aggregation, up to ~5.17 Gbps.
• Uplink: 256QAM, 2CC UL etc. <br> Wi-Fi 6E, • Bluetooth 5.4.
• GNSS Supports multi-GNSS: GPS (L1CA, L5,
• L1C), BeiDou, Galileo, Glonass, QZSS, NavIC etc.
Video Encoding / Decoding Encode:
•AVC (H.264), HEVC (H.265), up to 4K @ 60 fps. •Playback: Also supports VP9, AV1 besides the standard codecs, also up to 4K @ 60 fps.
Power Efficiency Enhancements
• Larger in-chip caches (L2, L3, SLC) to reduce memory accesses.
• 44% lower peak power use (vs previous generation) for CPU performance targets.
• GPU improvements reduce memory bandwidth and power.
• UltraSave 3.0+ for 5G power efficiency.
What's New / What’s Better
All Big Core: Unlike designs that mix in small (efficiency) cores, the 8400 uses only “big” high-performance lanes. This suggests MediaTek is betting on performance even under load, but expects power efficiency improvements elsewhere (caching, power control) to offset battery drain.
More Cache: L2, L3 and SLC caches are significantly enlarged, to reduce latency and increase performance per watt.
Generative AI & Agentic AI: More software and tooling focus here. The hardware (NPU 880) is able to accelerate newer AI models.
Graphics Efficiency: The G720 MC7 plus Frame Rate Converter helps maintain smoother gaming and reduce power use in high-intensity graphics tasks.
Potential Trade-offs / Things to Watch
Using all big cores may challenge thermal design and battery life in phones, especially under sustained loads (gaming, 4K recording). The gains from caching & power control need to be well-implemented by manufacturers.
Supporting high refresh rates, high resolution, multiple cameras, etc., still depends heavily on the cooling solution, battery capacity, actual phone design.
Real-world AI performance depends also on software optimization, driver support, and whether apps leverage the advanced NPU + AI engine features.
Real-World Implications
For users, this chip means:
Smartphones with very strong performance, especially for demanding tasks: games, video editing, AI-assisted features, etc.
Better image quality, especially under difficult conditions (low light, zoom) thanks to the imaging pipeline enhancements.
Smoother experiences in multitasking, high refresh rate displays.
Possibly better battery life for “typical” usage (browsing, social media, etc.) thanks to more efficient architectures, though under heavy usage the power draw could still be high.
Conclusion
The MediaTek Dimensity 8400 marks a shift: pushing premium performance without sacrificing too much on power efficiency, and bringing generative AI capabilities tightly integrated into the SoC. It’s well-suited for phones targeting the high end (flagship or near-flagship), especially as features like high refresh rate displays, heavy camera use, and on-device AI become more commonplace.
