Introduction
Few things capture the imagination of the PC gaming community quite like a crossover between iconic game design and custom hardware. Years ago, the skin-and-accessory giant dbrand teased a spectacular, limited-edition custom Steam Machine chassis designed to look exactly like the Aperture Science Weighted Companion Cube from the Portal universe. Unsurprisingly, copyright hurdles and intellectual property friction with Valve ultimately forced dbrand to shelve the project, leaving SFF (Small Form Factor) enthusiasts heartbroken.
Fast forward to 2025, and the open-source DIY community has done what corporate legal teams could not. A talented 3D printing enthusiast has fully reverse-engineered, optimized, and released printable STL files for a custom Mini-ITX chassis heavily inspired by that cancelled dbrand design. If you have a 3D printer, some patience, and a passion for custom PC building, you can now assemble this legendary Companion Cube Steam Machine right on your desk.
In this comprehensive guide, we will break down the history of this cancelled masterpiece, explore the hardware you need to build it, and review the best components to ensure your custom cube does not end up in an actual Aperture Science Incinerator due to overheating.
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The Backstory: From Cancelled Hype to DIY Triumph
When Valve first launched the Steam Machine initiative, it sparked a golden age of compact console-like PC cases. dbrand’s planned Companion Cube enclosure was set to be the crown jewel of this movement. It featured intricate, multi-layered paneling, glowing pink LED accents, and a dense layout that maximized airflow while maintaining the exact proportions of Portal’s most beloved inanimate object.
Unfortunately, because the design directly utilized Valve's protected intellectual property, commercializing the case became a legal minefield. The project was quietly mothballed, existing only in high-resolution render archives and the dreams of SFF forum users.
Now, thanks to high-tolerance consumer 3D printers and CAD wizardry, the design has been reborn as a non-commercial, completely free DIY project. By splitting the chassis into modular, interlocking pieces, the creator has made it possible to print this complex shape on standard desktop 3D printers without needing industrial-grade SLS machines.
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The Printer & Materials You Need
Building a PC case is not like printing a decorative toy. The plastics used must withstand the ambient internal temperatures of high-performance PC hardware. Standard PLA will warp, sag, and deform under sustained gaming loads. To build a reliable Companion Cube, you need the right tools.
1. The 3D Printer: Bambu Lab P1S (~$599)
To print parts in heat-resistant materials like ABS or ASA, you need a stable, enclosed 3D printer. The Bambu Lab P1S is currently the gold standard for hobbyists looking for industrial-grade reliability. Its fully enclosed chamber keeps ambient temperatures stable, preventing warp-prone filaments from lifting off the build plate during long prints.2. The Filament: eSUN ABS+ Filament (~$25 per kg)
Do not use PLA for this project. Instead, opt for eSUN ABS+ Filament in grey, white, and pink. ABS+ offers excellent thermal resistance (withstanding temperatures up to 100°C) and is much easier to print than traditional ABS. It can also be acetone-vapor smoothed for that premium, injection-molded look that dbrand originally promised.---
Recommended PC Hardware for the Companion Cube
Because this is a compact Mini-ITX build, component selection is critical. You need parts that offer high performance-per-watt to keep thermals manageable inside a 3D-printed enclosure. Here is our curated component list for a flawless 2025 build:
Motherboard: ASUS ROG Strix B760-I Gaming WiFi (~$220)
To power this compact beast, the ASUS ROG Strix B760-I Gaming WiFi is an exceptional choice. It offers robust VRMs, support for DDR5 memory, and excellent onboard M.2 cooling. Its clean black aesthetic and pre-mounted I/O shield make it incredibly easy to install within the tight confines of a 3D-printed frame.CPU Cooler: Noctua NH-L9i-17xx chromax.black (~$55)
Space is at an absolute premium in this chassis. The Noctua NH-L9i-17xx is a legendary low-profile cooler that stands just 37mm tall. It provides whisper-quiet operation and plenty of thermal headroom for mid-range gaming CPUs like the Intel Core i5-13400F or i5-14400, ensuring your Companion Cube remains cool and quiet.Power Supply: Corsair SF750 80+ Platinum (~$180)
SFF builds require clean cable management, and there is no better power supply for this than the Corsair SF750. It is highly efficient, runs completely silent at low-to-medium loads, and features premium, individually sleeved flexible cables that make routing in tight spaces a breeze.---
Printing and Assembly Tips
If you are ready to tackle this project, keep these crucial assembly tips in mind:
1. Use Threaded Brass Inserts: Never screw PC components directly into 3D-printed plastic. Use a soldering iron to melt M3 brass threaded inserts into the pre-designed pilot holes on the chassis frame. This ensures your motherboard and GPU are securely mounted and can be disassembled without stripping the plastic. 2. Optimize Airflow Paths: The Companion Cube design utilizes the corner brackets of the cube as hidden exhaust vents. Ensure your internal cabling is tied down tightly so it does not block these vital pathways. 3. Integrate Addressable RGB: To get that authentic Aperture Science glow, route a 5V ARGB LED strip along the inner seams of the pink heart panels. You can plug this directly into the ASUS ROG Strix motherboard to sync the pulsing pink glow with your favorite games.
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