Compact micro-ATX PC build: a researched air-cooled configuration
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The Lian Li A3 is the case I’d choose for this compact micro-ATX build. Pair it with the Ryzen 5 9600X, a short ASUS Dual RX 9060 XT and air cooling, then lay out the PSU leads while the small headers are still easy to reach.
Compare this fixed configuration with the full quiet and compact build guide. Use the compact motherboard choices and compact graphics cards before changing the basket.
I like micro-ATX as a compact-build middle ground: useful board space in a case that takes up less of the desk. For this A3 layout I’d use a short ASUS Dual card, a 140mm-long PSU and a tower air cooler, with the power leads planned early.
The H5 Flow build is my easier route when access and room for later changes matter more than size. Its ATX motherboard belongs in the larger case; the A3 list uses a micro-ATX board.
The parts I’d use
| Part | Choice | Condition |
|---|---|---|
| Case | Lian Li A3 mATX wood-front | Verify exact panel version, supplied brackets and fan package. |
| Board | Gigabyte B650M DS3H | Micro-ATX DDR5; match hardware revision, Ryzen 9600X support and required BIOS. No assumed Wi-Fi. |
| CPU | Ryzen 5 9600X | Separate AM5 cooler required. |
| RAM | Crucial Pro 32GB DDR5-6000 | 2×16GB CP2K16G60C36U5B; compare compatible kits if the offer is poor. |
| GPU | ASUS Dual RX 9060 XT 16GB | Short 202mm model; still allow power-lead and fan space. |
| SSD | Crucial P310 2TB 2280 | Check board slot and heatsink procedure. |
| Cooler | Peerless Assassin 120 SE | Nominal 155mm body; installed fan must remain inside case clearance. |
| PSU | RM850e 2025 | ATX option with 140mm body; a suitable lower-output or SFX option may improve cost/layout. |
| Case cooling | Start with a rear exhaust and a clear air path through the cooler | Include the case fans in the parts budget and connect them to the board’s fan headers. |
Fit conditions that must be resolved
The B650M DS3H specification identifies a 24.4cm-square micro-ATX board. Use the support page for the actual revision and confirm the required BIOS before buying. Include Wi-Fi separately if needed.
The A3 specification and layout diagrams give 165mm CPU-cooler clearance and configuration-dependent GPU space. Compare that with the cooler’s actual fan position, not only its nominal body height.
The short GPU reduces length pressure, but the ATX PSU bracket and leads still need a mapped route. Verify the selected bracket position in the manual. Do not infer safe simultaneous clearance from the separate maximum figures.
Assembly and airflow plan
Fit and route difficult leads while the small headers remain accessible. Keep the graphics intake clear and avoid buying bottom fans before checking thickness space. Follow the case maker’s supported air-cooling layout.
Map the A3’s graphics, cooler and any radiator positions together, route bulky leads first and leave filter-removal room.
Before ordering
Complete the compact fit record, add needed fans and network equipment, then enter the offers in the calculator.
If a required bracket, fan clearance or cable route cannot be confirmed, choose another layout before purchasing.