GUIDE
Small PC build guide: Mini-ITX in 25 litres or less
A small PC takes up less desk space and is easier to move, but every part has to fit a tighter set of limits. BuildPC treats a case of 25 litres or less as “small”. These are the checks that matter most.
1. Motherboard: Mini-ITX
Small cases usually take only Mini-ITX boards. These typically have two memory slots instead of four and one slot for a graphics card, so choose the memory size you want from the start. For example, the MSI MPG B650I EDGE WIFI has two DDR5 slots and two M.2 slots for SSDs.
2. CPU cooler height
This is the limit people miss most often. The Cooler Master NR200P V2 (18.25 L) allows CPU coolers up to 67 mm tall, which rules out large tower coolers. Low-profile coolers fit, but makers such as Noctua warn that their slimmest models are not suitable for CPUs that produce a lot of heat. That is why BuildPC’s small builds use a 65 W six-core CPU with the cooler included in its box, rather than a hotter eight-core chip. Check the height of any cooler against your case limit.
3. Graphics card length and thickness
Check both. The NR200P V2 takes cards up to 334 mm long, or up to 356 mm for cards no thicker than 73 mm, and up to three slots thick. A Sapphire PULSE RX 9060 XT 16GB is 240 mm long, and an MSI RTX 5060 Ti 16G VENTUS 2X OC PLUS is 227 mm long and 41 mm (two slots) thick, so both fit comfortably.
4. Power supply: SFX or SFX-L
Small cases rarely take a full ATX power supply. Check which sizes the case supports and the maximum length. The Corsair SF750 (2024) is an SFX unit 100 mm deep with two 8-pin graphics plugs and a native 12V-2×6 cable. The power supply guide explains how to size the wattage.
5. Heat and noise
Less space means less airflow. A small PC with a powerful graphics card will usually run warmer and louder than the same parts in a larger case. If you need the fastest CPU for long, heavy workloads such as video exports, a standard-size build is the better choice.
A verified example
BuildPC’s small gaming starter build uses: AMD Ryzen 5 7600 (boxed, with cooler), MSI MPG B650I EDGE WIFI, Kingston FURY Beast 32 GB DDR5-6000 (2 × 16 GB), Sapphire PULSE RX 9060 XT 16 GB, Kingston NV3 1 TB SSD, Corsair SF750 (2024) and the Cooler Master NR200P V2. Every part passes the builder’s socket, memory, size and power checks. In the builder, choose Size: Small to load it, or the matching small builds for office, editing and local AI.
Specifications come from manufacturer pages and were last reviewed in October 2026. Always confirm them on the manufacturer’s site before buying. BuildPC has no affiliate links and does not track live prices.