How to Build a Powerful Mini-ITX Gaming PC for 4K Performance

There’s something uniquely satisfying about building a SFF Mini-ITX PC gaming PC that’s not just powerful but also compact enough to fit on a small desk or shelf. But let’s be real—packing that much power into a small form factor (SFF) PC isn’t exactly a walk in the park. Between managing thermals, finding compatible components, and staying within budget (or at least trying to), the process can feel overwhelming. That’s where this build by ETA Prime comes in—a testament to what’s possible when innovative hardware meets thoughtful design.

In this guide, ETA Prime takes you through the creation of what might just be the most powerful SFF Mini-ITX gaming PC they’ve ever built. From the sleek Lian Li M3 case to the powerhouse AMD Ryzen 9 9800X3D CPU and NVIDIA GeForce RTX 590 GPU, every component was chosen with performance and efficiency in mind. But this isn’t just about raw power—it’s about overcoming the unique challenges of building a high-end system in a compact space. Whether you’re a seasoned builder or just someone curious about what goes into a top-tier SFF PC, you’re in for a deep dive into the highs, lows, and everything in between.

Powerful SFF Mini-ITX PC Project

TL;DR Key Takeaways :

The build features premium components, including the AMD Ryzen 9 9800X3D CPU and Nvidia GeForce RTX 590 GPU, delivering exceptional 4K gaming performance with advanced features like ray tracing and DLSS.
The compact Lian Li M3 case balances size and airflow, accommodating high-performance hardware while maintaining efficient thermal management with a 240mm AIO liquid cooler.
Performance benchmarks highlight impressive results, such as a Geekbench 6 multi-core score of 18,440 and a 3DMark Time Spy graphics score of 49,518, showcasing its capability for demanding workloads.
Gaming tests at 4K Ultra settings demonstrate smooth gameplay, with standout results like 260 FPS in Cyberpunk 2077 (with DLSS) and 94 FPS in Starfield, though the GPU shows limitations in non-DLSS scenarios.
While the build excels in performance, its high cost, power consumption (603W during gaming, 831W peak), and thermal challenges make it best suited for enthusiasts rather than everyday users.

Case and Build Design: Compact Yet Capable

The backbone of this build is the Lian Li M3 case, a compact chassis with a 26.3L volume that strikes a balance between size and airflow. Its modular design simplifies cable management and accommodates high-performance components, making it an excellent choice for an SFF build. The decision to use a full-sized ATX power supply—the 1,000W XPG Core Reactor 2 PSU—introduced certain trade-offs. Specifically, the cooling solution was limited to a 240mm all-in-one (AIO) liquid cooler to fit within the case’s constraints.

Despite these challenges, the modularity of the Lian Li M3 case enabled efficient installation of premium components. The case’s design ensures that airflow and thermal performance remain uncompromised, even in a compact space. This careful balance between size and functionality is a cornerstone of the build’s success, allowing it to house powerful hardware without sacrificing cooling efficiency.

Core Components: Power Meets Precision

At the heart of this SFF PC is the AMD Ryzen 9 9800X3D CPU, renowned for its exceptional gaming performance and energy efficiency. Paired with the Nvidia GeForce RTX 590 GPU, specifically the Zotac Gaming AMP Extreme Infinity Edition, this combination delivers smooth 4K gaming with advanced features such as ray tracing and DLSS. Together, these components form the foundation of a system designed to excel in both gaming and productivity tasks.

Additional components include:

Memory: 48GB of Viper Extreme 5 RAM, clocked at an impressive 7,800MHz, ensures seamless multitasking and gaming performance.
Storage: A 2TB SK Hynix Platinum P41 M.2 SSD provides ample storage capacity and ultra-fast read/write speeds, significantly reducing load times.

This carefully selected hardware combination ensures top-tier performance, making the system suitable for demanding workloads and immersive gaming experiences.

SFF Mini-ITX PC Build Process by ETA Prime

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Discover other guides from our vast content that could be of interest on Small Form Factor (SFF) PC.

Performance Benchmarks: Numbers That Impress

To evaluate the system’s capabilities, a series of benchmarking tools were employed. The results highlight the impressive power packed into this compact build:

Geekbench 6: Single-core score of 3,198, Multi-core score of 18,440.
3DMark Time Spy: Graphics score of 49,518.
Power Consumption: 603W during gaming, peaking at 831W under extreme load.

These benchmarks underscore the system’s ability to handle demanding applications, from AAA gaming to intensive productivity tasks. The high scores reflect the synergy between the AMD Ryzen 9 9800X3D CPU and Nvidia GeForce RTX 590 GPU, showcasing their ability to deliver exceptional performance in a compact form factor.

Gaming Performance: 4K Excellence

The system was tested with several AAA games at 4K Ultra settings, demonstrating its ability to deliver smooth and immersive gameplay. Key results include:

Starfield: 94 FPS average, offering a fluid and visually stunning experience.
Cyberpunk 2077: 260 FPS with DLSS and frame generation enabled, highlighting the GPU’s capabilities in using advanced technologies.
God of War Ragnarok: 150 FPS average, making sure a seamless and cinematic gaming experience.
Spider-Man 2: 72 FPS with DLSS and ray tracing, balancing visual fidelity and performance.

While the system excelled in most scenarios, the GPU’s limitations became evident in certain games that lacked DLSS support. This highlights the importance of using modern technologies to optimize performance in graphically demanding titles.

Thermals and Power Efficiency: Managing the Heat

Thermal management is a critical consideration in any SFF build, and this system performs admirably in this regard. The 240mm AIO cooler keeps the AMD Ryzen 9 9800X3D CPU at an average temperature of 63°C, with peaks reaching 82°C under heavy load. Similarly, the Nvidia GeForce RTX 590 GPU maintains an average temperature of 62°C, peaking at 76°C during intense gaming sessions.

The system’s high power draw—603W during gaming and 831W at peak load—necessitated the use of a 1,000W PSU. While this ensures stability and reliability, it also underscores the energy demands of high-performance hardware in a compact form factor. Effective thermal management and power efficiency are essential to maintaining system stability and longevity, particularly in SFF builds where space constraints amplify these challenges.

Cost and Practicality: A Premium Investment

This build represents the pinnacle of SFF gaming performance, but it comes with a significant financial investment. The Nvidia GeForce RTX 590, in particular, is a costly component that contributes heavily to the overall expense. For users seeking a more budget-friendly alternative, the RTX 4070 offers excellent performance for 1440p gaming at a fraction of the price.

Additionally, the high power requirements and thermal considerations make this build less practical for everyday users. It is best suited for enthusiasts who prioritize performance and are willing to invest in premium components. For those seeking a balance between performance and affordability, exploring mid-range alternatives may be a more viable option.

Media Credit: ETA PRIME

Filed Under: Hardware, Top News

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