Smallest ATX Cases: A Comprehensive Guide

Finding the smallest ATX case involves balancing compact size with the ability to accommodate standard ATX components, including mid-size GPUs like the NVIDIA GeForce RTX 4070. While the ATX standard inherently imposes a minimum size, several cases on the market push the boundaries of compact design. Here's a detailed look at some of the smallest ATX cases available, considering their volume, component support, and compromises.

Defining "Smallest"

For this discussion, "smallest" is defined by the total volume of the case, measured in liters. Smaller volume is better, but it's crucial to ensure the case can still support a standard ATX motherboard, a mid-size GPU (like an RTX 4070), and other necessary components. It's also important to note that the ATX standard itself sets a minimum size requirement, so there are limits to how small an ATX case can be without compromising on compatibility or essential features.

Top Compact ATX Cases

Here are some of the smallest ATX cases, ranked by approximate volume, along with their key features and compromises:

1. N-ATX Case

• Volume: Approximately 14 liters
• Dimensions: Not specified, but designed to be extremely compact.
• Component Support:
  • Motherboard: ATX
  • GPU: Supports mid-size GPUs like the RTX 4070, but may not fit larger cards like the RTX 4090.
  • Cooling: Supports up to 120mm fans, designed for space efficiency.
  • Power Supply: Typically requires an SFX power supply for optimal space efficiency.
• Compromises:
  • GPU Length: Limited to mid-size GPUs.
  • Power Supply: Requires an SFX power supply.
  • Expansion Slots: May have limited expansion slots compared to larger ATX cases.
• Notes: The N-ATX case is designed to be as small as possible while still supporting ATX components. It is a good choice for those who need a compact ATX setup.

2. Cooler Master MasterBox Q300L

• Volume: Approximately 22.6 liters
• Dimensions: 385 x 210 x 400 mm (15.2 x 8.3 x 15.8 inches)
• Component Support:
  • Motherboard: ATX
  • GPU: Supports GPUs up to 360mm.
  • CPU Cooler: Supports CPU coolers up to 157mm in height.
• Compromises:
  • Limited internal space, which can make cable management challenging.
  • Restrictions on CPU cooler height.
  • Fewer cooling options compared to larger cases.
• Notes: The Q300L is a budget-friendly option with a focus on compact size.

3. Fractal Design Meshify C Mini

• Volume: Approximately 31.4 liters
• Dimensions: 451 x 210 x 409 mm (17.8 x 8.3 x 16.1 inches)
• Component Support:
  • Motherboard: ATX
  • GPU: Supports GPUs up to 315mm without a front fan.
• Compromises:
  • GPU length limitations.
  • Fewer drive bays, limiting storage options.
  • Less space for advanced cooling configurations.
• Notes: The Meshify C Mini is a good option for those who want a balance of size and airflow.

4. Thermaltake V21

• Volume: Approximately 31.2 liters
• Dimensions: 420 x 236 x 390 mm (16.5 x 9.3 x 15.3 inches)
• Component Support:
  • Motherboard: ATX
• Compromises:
  • Challenging cable management in tight spaces.
  • Limited cooling options for high-end components without modification.
  • Performance may vary based on airflow configuration.
• Notes: The V21 offers a unique cube-like design.

5. Phanteks Eclipse P300A

• Volume: Approximately 31.1 liters
• Dimensions: 442 x 210 x 445 mm (17.4 x 8.2 x 17.5 inches)
• Component Support:
  • Motherboard: ATX
  • GPU: Supports GPUs up to 400mm.
• Compromises:
  • Limited drive bays, which may require external storage solutions.
  • Slightly heavier due to the materials used.
• Notes: The P300A is known for its good airflow and build quality.

6. Fractal Design Meshify C

• Volume: Approximately 35.5 liters
• Dimensions: 399 x 217 x 409 mm
• Component Support:
  • Motherboard: ATX
• Compromises:
  • Limited space for cable management.
  • Slightly reduced airflow compared to larger cases, though the mesh design helps.
  • Limited space for additional storage drives.
• Notes: The Meshify C is a popular choice for its balance of size and airflow.

7. Cooler Master MasterBox NR400

• Volume: Approximately 35.6 liters
• Dimensions: 411 x 208 x 418 mm
• Component Support:
  • Motherboard: ATX
• Compromises:
  • Limited space for cable management.
  • May have reduced airflow due to its compact size.
  • Limited space for additional storage drives.
• Notes: The NR400 is a compact case with a focus on simplicity.

8. Phanteks Eclipse P300A (Revisited)

• Volume: Approximately 37.8 liters (Note: This volume differs slightly from the previous listing, indicating variations in measurements or model versions)
• Dimensions: 406 x 206 x 458 mm
• Component Support:
  • Motherboard: ATX
• Compromises:
  • The front panel can be a bit tricky to remove for cleaning.
  • Limited space for cable management and additional storage.
  • The compact design might make installation of larger CPU coolers challenging.
• Notes: The P300A is a popular choice for its balance of size and airflow.

9. NZXT H510

• Volume: Approximately 38.7 liters
• Dimensions: 428 x 210 x 435 mm
• Component Support:
  • Motherboard: ATX
• Compromises:
  • Limited airflow due to the solid front panel.
  • Limited space for cable management.
  • The compact design might limit the size of the CPU cooler you can use.
• Notes: The H510 is known for its minimalist design.

10. Fractal Design Torrent Compact

• Volume: Approximately 42 liters
• Component Support:
  • Motherboard: ATX
  • GPU: Supports GPUs up to 330mm.
• Compromises:
  • Limited radiator options.
  • Tight cable management.
• Notes: The Torrent Compact is designed for high airflow.

11. Lian Li Lancool 205M

• Volume: Approximately 43 liters
• Component Support:
  • Motherboard: ATX
  • GPU: Supports GPUs up to 350mm.
• Compromises:
  • Limited water cooling options.
  • Might be tight with longer PSUs.
• Notes: The Lancool 205M is a compact case with a focus on airflow.

12. Phanteks Eclipse G360A

• Volume: Approximately 44 liters
• Component Support:
  • Motherboard: ATX
• Compromises:
  • Limited space for top radiators.
• Notes: The G360A is known for its good airflow and modern design.

13. Corsair 4000D Airflow

• Volume: Approximately 48.6 liters
• Dimensions: 453 x 230 x 466 mm
• Component Support:
  • Motherboard: ATX
• Compromises:
  • Slightly larger than other cases on this list, but still considered compact.
  • Limited space for cable management.
  • May require more planning for component placement due to its size.
• Notes: The 4000D Airflow is a popular choice for its excellent airflow and build quality.

Key Considerations When Choosing a Compact ATX Case

When selecting a compact ATX case, consider the following:

• Cooling Efficiency: Smaller cases can have limited airflow, so ensure the case has adequate ventilation or supports your preferred cooling solution (air or liquid).
• Internal Layout: A well-designed internal layout can make cable management easier and improve airflow.
• Maximum Supported Dimensions: Always check the maximum supported dimensions for GPUs, CPU coolers, and radiators to ensure compatibility with your components.
• Component Compatibility: Verify that the case supports your specific components, including the motherboard, GPU, power supply, and storage devices.
• Build Quality: Look for cases made from durable materials that can withstand the rigors of daily use.
• User Reviews: Check user reviews and community feedback to get a better understanding of the case's strengths and weaknesses.

Compromises of Compact ATX Cases

Compact ATX cases often come with compromises, including:

• Limited Space: Reduced space for cable management, storage drives, and expansion cards.
• Cooling Restrictions: Limited space for large CPU coolers and radiators, which can affect cooling performance.
• GPU Length Limitations: Some compact cases may not support longer GPUs.
• Power Supply Limitations: Some cases may require an SFX power supply for optimal space efficiency.
• Airflow Restrictions: Smaller cases may have reduced airflow, which can lead to higher temperatures.

Conclusion

The N-ATX case stands out as the smallest ATX case, with a volume of approximately 14 liters, but it requires an SFX power supply and has limitations on GPU length. Other compact options, like the Cooler Master MasterBox Q300L, Fractal Design Meshify C Mini, Thermaltake V21, and Phanteks Eclipse P300A, offer a balance of size and component support. When choosing a compact ATX case, carefully consider your specific needs and the compromises involved. Always check the manufacturer's specifications and user reviews to ensure compatibility with your components and desired performance.

Remember that the market is constantly evolving, and new cases are frequently released. Always consult recent reviews and the manufacturer's official website for the most up-to-date information.