Showstopper Build: Greyscale — Building a Custom-Looped ITX PC that Pushes the Form Factor to Its Limits

Why It Matters

This demonstrates that extreme performance PCs can be realized in SFF enclosures, expanding options for gamers and creators who value space efficiency without compromising power. It also validates the viability of custom‑loop cooling in tight cases, influencing future case designs and component integration.

Key Takeaways

• NCase M3 houses RTX 5090 and Ryzen 9 9950X3D in 19‑liter case
• Custom water‑loop required to cool 600 W GPU behind glass side panel
• 1000 W SFX Platinum PSU powers the ultra‑dense component lineup
• Build demonstrates feasibility of extreme SFF gaming rigs for enthusiasts

Pulse Analysis

The small‑form‑factor (SFF) market has long been dominated by modest‑performance builds, but the demand for compact yet powerful rigs is accelerating as urban living spaces shrink and remote work drives a need for versatile workstations. NCase, a niche manufacturer that partners with Lian Li for precision‑engineered aluminum cases, has cultivated a reputation for pushing the envelope of what an ITX chassis can hold. By selecting the M3—a 19‑liter case with a glass side panel—the Tom’s Hardware team set out to test whether today’s most demanding components could coexist without sacrificing thermal stability.

Achieving that goal required a meticulously engineered custom water‑loop. The RTX 5090 Suprim alone dissipates roughly 600 W, a heat load that would overwhelm any conventional airflow solution in a sealed case. The team employed a high‑flow pump, dual‑radiator configuration hidden behind the glass, and a GPU water block designed for the 5090’s massive die. Coupled with a 1000 W SFX Platinum power supply and DDR5‑7200 memory, the loop maintains sub‑80 °C GPU temperatures under load while preserving the aesthetic of a clear side view. This engineering feat underscores how advanced cooling can unlock performance ceilings previously thought exclusive to full‑tower builds.

The successful execution of this build signals a shift for both enthusiasts and manufacturers. It proves that ultra‑high‑end gaming and content‑creation workloads can be housed in a footprint small enough for cramped apartments or minimalist desks, potentially expanding the market for premium SFF cases and bespoke cooling kits. As component power densities continue to rise, we can expect more case makers to integrate modular cooling pathways and reinforced glass panels, making extreme performance a mainstream expectation rather than a niche curiosity.