Building a Mini-ITX PC offers a unique blend of performance and space efficiency. Unlike larger mid-tower or full-tower builds, a Mini-ITX system fits on a desk, beside a TV, or inside a carry-on bag. However, the small footprint introduces constraints in component compatibility, cooling, and cable management that require careful planning. This guide provides a step-by-step, evidence-based approach to assembling a Mini-ITX computer, with specific recommendations for parts available at Taiwan retailers such as 原價屋 (CoolPC), 欣亞 (Singya), and PChome 24h. Whether you are building a budget office machine or a high-end gaming rig, the principles here apply to most modern Mini-ITX setups.

Before starting, we strongly recommend reading our Complete Guide to Buying and Building a PC in Taiwan for general purchasing and assembly advice. That article covers warranty, VAT, and store policies that directly affect Mini-ITX builders in Taipei, Kaohsiung, and elsewhere.

1. Choosing the Right Mini-ITX Case

The case is the single most important decision in a Mini-ITX build. It determines which motherboard, cooler, power supply, and graphics card you can use. Cases in this form factor range from 4 litres to over 20 litres. Below is a breakdown of popular Mini-ITX case categories with real models and prices as of early 2025.

1.1 Sandwich‑Layout Cases (Console‑Style)

These cases place the GPU on a riser cable parallel to the motherboard, enabling a very slim profile. They are ideal for desks with limited depth.

  • Cooler Master NR200P, NT$2,690 at CoolPC. Accepts up to 155mm CPU coolers, 330mm GPUs, and SFX/SFX-L PSUs. The NR200P is one of the most flexible Mini-ITX cases, with excellent airflow and support for 240mm AIO liquid coolers.
  • Lian Li A4-H2O, NT$3,990 at Singya. A 11-litre aluminium case that supports 240mm AIO coolers and 3-slot GPUs up to 322mm. It requires an SFX power supply.
  • Fractal Design Terra, NT$4,490 at PChome. A wooden-accented case with adjustable spine to accommodate either a taller CPU cooler (up to 77mm) or a thicker GPU (up to 3-slot). Maximum GPU length is 335mm.

1.2 Tower‑Style Cases

These cases resemble a miniaturised traditional tower, often with a vertical motherboard orientation. They allow larger CPU air coolers but typically restrict GPU length.

  • SilverStone SUGO 16, NT$2,390. Supports mATX and Mini-ITX motherboards, ATX PSUs, and GPUs up to 330mm. The SUGO 16 is a budget-friendly option with mesh side panels.
  • Jonsbo C2, NT$1,890 at CoolPC. A 13-litre aluminium case that fits Mini-ITX boards, SFX PSUs, and GPUs up to 240mm. Limited CPU cooler height of 80mm restricts air cooler choices to low-profile models.

1.3 Ultra‑Compact Cases

For absolute space savings, these cases often require Flex ATX power supplies or external power bricks. They are not recommended for first-time builders.

  • Velka 3, ~NT$4,500 (import). A 3.9-litre case that fits a Mini-ITX board, Flex ATX PSU, and a GPU up to 175mm. CPU cooler height max is 37mm, limiting you to stock or low-profile coolers.
  • InWin Chopin, NT$2,290. Built-in 150W power supply, no discrete GPU support. Suitable for office or HTPC builds with an APU.

When choosing a case, always check the manufacturer’s specifications for CPU cooler clearance, GPU length, and PSU form factor. Use our Mid-Range Gaming PC guide for component suggestions that fit inside these cases.

2. Selecting the Mini-ITX Motherboard

Mini-ITX motherboards measure 170mm x 170mm and have a single PCIe x16 slot. They are available for AMD AM5, Intel LGA1700, and older sockets. Key considerations are chipset, RAM slots (usually two), M.2 slot count, and rear I/O ports.

2.1 AMD AM5 Boards

  • ASRock B650E PG-ITX WiFi, NT$7,990. Features PCIe 5.0 for both GPU and M.2, USB4 support, and WiFi 6E. Two DDR5 DIMM slots, one PCIe 5.0 M.2, and one PCIe 4.0 M.2.
  • Gigabyte B650I AORUS Ultra, NT$6,490. Similar feature set but with a PCIe 5.0 M.2 and PCIe 4.0 GPU slot. Includes a 2.5GbE LAN and WiFi 6E.
  • ASUS ROG STRIX B760-I, NT$6,990 (Intel LGA1700). Two M.2 slots (one PCIe 5.0), DDR5 support, and a robust VRM design for overclocking.

2.2 Intel LGA1700 Boards

  • MSI MPG B760I EDGE WiFi, NT$5,990. Two M.2 slots, DDR5, WiFi 6E, and a PCIe 5.0 x16 slot. Good for i5 and i7 builds.
  • ASRock H610M-ITX, NT$3,290. Budget option with DDR4 support, one M.2 slot, and limited VRM. Suitable for i3 or low-power i5 chips.

For a budget-oriented Mini-ITX build, see our Budget PC Build 2024 for CPU and RAM pairings that work well with these boards.

3. CPU, Cooler, and RAM Constraints

Mini-ITX builds require careful thermal management. The small interior means less airflow and limited cooler height. We recommend CPUs with a TDP of 65W or lower for air cooling, or up to 105W if using a 240mm AIO.

3.1 CPU Recommendations

  • AMD Ryzen 5 7600 (65W), NT$7,000. Excellent for gaming and productivity. Comes with a stock Wraith Stealth cooler that fits in most cases with 90mm+ clearance.
  • AMD Ryzen 7 7800X3D (120W), NT$14,500. Best gaming CPU but requires a 240mm AIO or a high-end air cooler like the Noctua NH-L12S (70mm height).
  • Intel Core i5-14400 (65W), NT$6,500. Good value for mixed workloads. Stock cooler is adequate but noisy; a low-profile cooler like the Thermalright AXP90-X47 is recommended.
  • Intel Core i7-14700K (125W), NT$13,800. Requires a 240mm or 280mm AIO. Only fits in cases with top/bottom radiator support like the NR200P.

3.2 CPU Coolers

  • Noctua NH-L9a-AM5 (37mm), NT$1,650. Fits in ultra-compact cases like Velka 3. Suitable for 65W CPUs.
  • Thermalright AXP90-X53 Full Copper (53mm), NT$1,480. Excellent performance for its size, compatible with most sandwich-layout cases.
  • Noctua NH-D12L (120mm), NT$2,280. A 120mm tower cooler that fits in the NR200P and similar cases with 145mm clearance.
  • 240mm AIO (e.g., Cooler Master MasterLiquid ML240L V2), NT$2,490. Only for cases with radiator support.

3.3 RAM

Mini-ITX boards have two DIMM slots. Use a 2x16GB kit (32GB total) for most builds. Low-profile RAM (e.g., Corsair Vengeance LPX DDR5, height 33mm) is essential when using large air coolers. For Ryzen 7000 series, DDR5-6000 CL30 is the sweet spot. Prices: 32GB DDR5-6000 CL30 kits cost around NT$3,200 from G.Skill or Kingston.

4. Graphics Card (GPU) Selection and Fitment

GPU length and thickness are the main constraints. Most Mini-ITX cases support dual-slot GPUs up to 300-330mm. Triple-slot cards are possible only in wider cases like the NR200P or Fractal Terra (with the spine adjusted). Always measure the available space inside your case before buying.

  • NVIDIA GeForce RTX 4060 (dual-slot, 240mm), NT$10,500. Founders Edition or MSI Ventus 2X fits almost any case.
  • AMD Radeon RX 7800 XT (2.5-slot, 280mm), NT$15,000. Sapphire Pulse model fits most sandwich cases.
  • NVIDIA GeForce RTX 4070 Super (dual-slot, 267mm), NT$21,000. ASUS Dual model is a safe choice.
  • NVIDIA GeForce RTX 4090 (3-slot, 330mm+), NT$60,000+. Only fits in the largest Mini-ITX cases like the NR200P with a mesh side panel. Requires a 1000W SFX PSU.

For a high-end workstation with a powerful GPU, refer to our High-End Workstation Build guide for compatibility notes on workstation GPUs like the RTX 6000 Ada.

5. Power Supply (PSU) Form Factors

Mini-ITX cases typically require SFX or SFX-L power supplies. ATX PSUs only fit in a handful of cases like the SilverStone SUGO 16 or Cooler Master NR200 (with a bracket). SFX PSUs are smaller and more expensive.

5.1 Recommended SFX PSUs

  • Corsair SF750 (750W, SFX), NT$4,990. Platinum-rated, quiet fan, and reliable. Enough for an RTX 4070 Super + Ryzen 7.
  • Cooler Master V750 SFX Gold (750W), NT$4,290. Good alternative to the Corsair, with fully modular cables.
  • SilverStone SX1000 (1000W, SFX-L), NT$6,990. Necessary for RTX 4090 builds. SFX-L is 30mm longer than standard SFX; check case clearance.
  • EVGA SuperNOVA 650 GM (650W, SFX), NT$3,590. Budget option for builds with a 65W CPU and RTX 4060.

Always use individually sleeved cables or custom-length cables from a vendor like CableMod to reduce clutter. The less cable bulk, the better airflow and easier assembly.

6. Storage: M.2 SSDs and Cabling

Mini-ITX boards usually have one or two M.2 slots on the front, and sometimes one on the back. Use a single high-capacity NVMe SSD (2TB or 4TB) to avoid needing a second drive. Popular choices:

  • Samsung 990 Pro 2TB, NT$5,990. PCIe 4.0, excellent for gaming and content creation.
  • WD Black SN850X 2TB, NT$5,790. Similar performance, often on sale at PChome.
  • TeamGroup MP44L 2TB, NT$3,490. Budget-friendly PCIe 4.0 drive with good real-world speeds.

If your board has a rear M.2 slot, ensure your case has a cutout for it, or you may need to remove the motherboard to access it later. 2.5-inch SATA SSDs can be mounted on the case floor or side, but cable management becomes more challenging.

7. Assembly Tips for Mini-ITX

Building in a Mini-ITX case is more fiddly than a standard ATX build. Follow these steps in order to minimise rework.

  1. Prepare the motherboard outside the case: Install the CPU, RAM, M.2 SSD, and CPU cooler (if it is a low-profile air cooler) onto the motherboard before placing it in the case. For AIO coolers, attach the pump block after the motherboard is installed.
  2. Install the PSU first or last: In sandwich cases, installing the PSU first gives you room to route cables behind the motherboard tray. In tower cases, install the PSU last to avoid blocking access.
  3. Route cables before fixing the motherboard: Thread the 24-pin and 8-pin EPS cables through the case openings before screwing the motherboard down. Use zip ties to keep cables flat against the chassis.
  4. Connect front panel headers carefully: Mini-ITX cases often have separate power/HDD LED/audio cables. Use tweezers or a small screwdriver to plug them into the motherboard header. Refer to the motherboard manual for pin layout.
  5. Install the GPU last: For sandwich cases, the GPU slides into the riser cable after the motherboard is in place. For tower cases, you may need to remove the front fan bracket to angle the GPU in.
  6. Test the system before closing the case: Connect a monitor, keyboard, and power supply (outside the case if possible) to check that the PC posts. This saves you from having to disassemble if something is wrong.
  7. Manage thermals with fan curves: Use the BIOS or software like FanControl to set a quiet but effective fan curve. In small cases, exhaust fans are more important than intake fans.

For a more detailed walkthrough of the entire building process, including tool lists and troubleshooting, see our Complete Guide to Buying and Building a PC in Taiwan.

8. Example Build Configurations

Below are three example Mini-ITX builds at different price points, with estimated total costs from CoolPC and Singya in late February 2025.

8.1 Budget Office / HTPC (NT$15,000, NT$18,000)

  • Case: InWin Chopin (with 150W PSU), NT$2,290
  • Motherboard: ASRock H610M-ITX, NT$3,290
  • CPU: Intel Core i3-13100 (65W), NT$4,200
  • RAM: Kingston Fury Beast 2x8GB DDR4-3200, NT$1,490
  • Storage: TeamGroup MP44L 1TB, NT$2,090
  • OS: Windows 11 Home (OEM), NT$4,000 (optional)
  • Total (without OS): NT$13,360

8.2 Mid-Range Gaming (NT$45,000, NT$50,000)

  • Case: Cooler Master NR200P, NT$2,690
  • Motherboard: ASRock B650E PG-ITX WiFi, NT$7,990
  • CPU: AMD Ryzen 5 7600, NT$7,000
  • CPU Cooler: Thermalright AXP90-X53, NT$1,480
  • RAM: G.Skill Flare X5 2x16GB DDR5-6000 CL30, NT$3,200
  • GPU: NVIDIA GeForce RTX 4060 (MSI Ventus 2X), NT$10,500
  • PSU: Corsair SF750, NT$4,990
  • Storage: WD Black SN850X 2TB, NT$5,790
  • Total: NT$43,640

8.3 High-End Workstation / Gaming (NT$120,000+)

  • Case: Fractal Design Terra (or Lian Li A4-H2O), NT$4,490
  • Motherboard: ASUS ROG STRIX B760-I (Intel) or ASRock B650E PG-ITX (AMD), NT$6,990
  • CPU: Intel Core i7-14700K or AMD Ryzen 9 7950X, NT$13,800 / NT$17,500
  • CPU Cooler: 240mm AIO (Cooler Master ML240L V2), NT$2,490
  • RAM: Corsair Vengeance DDR5-6000 2x32GB, NT$5,800
  • GPU: NVIDIA GeForce RTX 4070 Ti Super (ASUS TUF), NT$28,000
  • PSU: Cooler Master V750 SFX Gold, NT$4,290
  • Storage: Samsung 990 Pro 2TB + 2TB SATA SSD, NT$5,990 + NT$3,500
  • Total (AMD variant): ~NT$72,060 without GPU upgrade

For alternative component lists at different budgets, consult our Budget PC Build 2024 and Mid-Range Gaming PC guides.

9. Cooling and Noise Considerations

Mini-ITX cases often run warmer than their larger counterparts. Follow these guidelines to keep temperatures in check:

  • Use at least one case fan as exhaust. In sandwich cases, a top exhaust fan (120mm or 140mm) is critical. In tower cases, a rear or side exhaust helps.
  • Consider an AIO liquid cooler for high-TDP CPUs. A 240mm AIO can handle up to 200W, but ensure the radiator is placed as an exhaust (top or side) to avoid dumping hot air inside.
  • Undervolt your CPU and GPU. Tools like Ryzen Master or MSI Afterburner can reduce power draw by 15-20% with minimal performance loss, which significantly lowers temperatures in a confined space.
  • Monitor temperatures during stress tests. Use Cinebench R23 and FurMark to verify that the CPU stays below 90°C and the GPU below 85°C. If temperatures exceed these, improve fan curves or reduce power limits.

Noise levels in Mini-ITX builds are often higher because smaller fans spin faster. Choose fans with a good reputation for low noise, such as Noctua NF-A12x25 (NT$1,050 each) or Arctic P12 PWM PST (NT$350 each).

10. Final Checks and BIOS Configuration

After assembly, enter the BIOS to enable XMP/EXPO for RAM speeds, set fan curves, and update the BIOS to the latest version. For AMD AM5 boards, enable Precision Boost Overdrive (PBO) if your cooling allows. For Intel boards, set the power limits to match your cooler’s capability (e.g., 125W PL1 for a 240mm AIO).

If you encounter boot failures, check the following:

  • RAM fully seated in both slots.
  • 24-pin and 8-pin EPS power connectors firmly attached.
  • CPU cooler fan spinning.
  • GPU power cables connected (if applicable).
  • Front panel power switch header oriented correctly.

For persistent issues, refer to the motherboard manual’s troubleshooting section or our Complete Guide to Buying and Building a PC in Taiwan, which includes a step-by-step POST troubleshooting flowchart.

Conclusion

Mini-ITX builds offer a rewarding challenge that results in a powerful, space-saving PC. By carefully selecting a case that fits your desired components, choosing a motherboard with the right features, and paying attention to cooling and cable management, you can build a system that is both compact and high-performing. The examples and recommendations in this guide are based on real products available in Taiwan as of early 2025. Always double-check dimensions and compatibility before purchasing, and don’t hesitate to ask store staff at CoolPC or Singya for assistance. Happy building!

Related Articles

  • The Complete Guide to Buying and Building a PC in Taiwan
  • Budget PC Build 2024
  • Mid-Range Gaming PC Build Guide
  • High-End Workstation Build Guide
  • Small Form Factor PC Cooling Guide
  • PSU Guide: SFX vs ATX for Compact Builds