Motherboard form factor, socket, cooler height, GPU length, PSU standards… Everything you need to verify before buying a single part, explained clearly with real-world examples.

Building a PC from scratch seems easy until you realize you bought an ATX motherboard for a Mini ITX case, or a cooler that stands 168mm tall for a chassis that only accepts 155mm. It’s not a rare situation — it’s one of the most common mistakes in hardware forums. This guide exists so it doesn't happen to you.

We analyze all key compatibilities using real, high-end components (Ryzen 7 9800X3D, Intel Core Ultra 9, RTX 5070, RX 9070 XT, Noctua NH-D15...) and show you how Hiditec BLOK and SKY chassis, C12 PWM, C20 PRO, and C40 PRO coolers, and the BZ PRO 750W PSU fit perfectly into real-world builds.

1. Motherboard Form Factor vs. Chassis: The First Filter

The form factor is the motherboard size standard. It defines physical dimensions and mounting hole placement. A chassis is designed to support one or several formats; if you pick a board larger than the case allows, it simply won't fit—the screws won't align and the I/O shield won't snap in.

The Simple Explanation: It’s like trying to fit a King-sized bed into a studio apartment. Physically impossible, no matter how hard you push.

2. CPU Socket vs. Motherboard: The Most Critical Point

The socket is the physical connector between the CPU and the motherboard. This is the most expensive mistake you can make because there is no "hack": if the socket doesn't match, the CPU won't fit. Period. Not even if the names sound similar.

The Simple Explanation: It’s like European vs. American power outlets. They do the same thing but have different shapes. An AMD processor won't fit an Intel board, and vice-versa. Even within brands, generations can be incompatible.

3. CPU Cooler vs. Chassis: The Most Forgotten Measurement

The air cooler is often the tallest component inside your PC. If its height exceeds the maximum clearance allowed by the case, the side panel won't close—or worse, you'll bend something trying to force it.

The Simple Explanation: Imagine buying a 7-foot Christmas tree when your ceiling is only 6.5 feet. It just doesn't work. Case manufacturers always list the maximum CPU cooler height, and even 1mm too much is a problem.

Hiditec Coolers: Real-World Specs

Which Hiditec cooler fits which case?

4. GPU Length vs. Chassis: The Graphics Card Must Fit

Modern high-end graphics cards in 2026 have grown significantly. An RTX 5070 can measure between 280mm and 340mm depending on the model (ASUS, MSI, Gigabyte…). Your chassis must support this length without the GPU hitting the front fans or drive cages.

The Simple Explanation: It’s like buying a sofa without measuring your living room door. The GPU has to fit into the "gap" from the PCIe slot to the front panel. If the card is longer than that gap, it’s not going in.

5. PSU Form Factor: Not All Power Supplies Fit All Cases

Most gaming mid-towers (like the BLOK and SKY) use the Standard ATX format for power supplies. However, compact cases use different formats like SFX or SFX-L, which are physically smaller and won't mount in a standard ATX bracket without an adapter.