Hands-on with Cooler Master’s Cosmos Alpha full-tower chassis – sliding, configurable interior makes for lots of possibilities

Cooler Master's Cosmos case has been a staple in the PC industry for almost 20 years. From the original Cosmos 1000 to the C700M flagship chassis, multiple iterations have combined bold, premium designs with aluminum external handles and a solid internal framework for mounting your precious hardware – with space for lots of it. Cooler Master's marketing team claims the new Cosmos Alpha, “... represents a significant step forward in the evolution of cases and what can be achieved with the latest generation of designs”. That's a bit over the top, but if you're a fan of big cases with room for lots of hardware, there's plenty to appreciate here.

For me, the star of the show is the FreeForm 2.0 platform, which evolved from a modular design to a more open, customizable platform, with Cooler Master describing it as freedom, scale, and personalization without compromise. In the Cosmos Alpha, this means the freedom to customize fan sizes and locations and the ability to adjust the motherboard. Eventually (they did not have an ETA), they’ll post measurements, dimensions, and tolerances on the Cooler Master website (and at Printables.com) so you can create 3D-printed items yourself or find other community-driven items to print for additional functionality.

The Cosmos Alpha is a step forward in design, keeping the familiar hands and feet, while maturing from the C700M to a simpler, more premium aesthetic. A hinged smoked-glass panel dominates one side, providing a tinted view of the inside, while a perforated panel covers the other. The IO panel features updated, ample connectivity, with six USB ports (two Type-C, four Type-A). You can install up to four 360mm radiators within the immense internal space ( 420mm is supported on the side, in front of the motherboard tray). Additionally, the Alpha also uses moveable fan mounts (so you can change fan size and location), and the motherboard tray slides back and forth so you can show off your hardware or make room for larger components (more on that later).

Cooler Master Cosmos Alpha Specifications

External Design and IO Panel

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Starting with the outside, this is a full-tower – a huge one measuring a whopping 26 x 13 x 25 inches (LxWxH), including the handles and feet. It feels very structurally sound, and even when empty, it is heavy. Be sure you have the room for it and a substantial base if it isn’t going to be on the floor, because this case weighs well over 70 pounds once populated with hardware.

The outer frame, with handles and feet, is grey/silver with a matte finish. All panels (front/rear, sides, and top) are black, providing a nice contrast. The front features a decorative plastic grille with large cutouts shaped like the Cooler Master logo, a dust filter behind it, and the two included SilentFlow 200mm fans. A similar grille, with smaller air gaps, is on the rear. Here we see a single Mobius 120mm fan (included), but the space holds up to three 120mm fans — yes, three rear exhaust fans. The ‘exoskeleton’ and grille on the back hide your cables exiting the rear, routing them out the bottom for a much cleaner look than most cases.

On top is a black mesh grille that runs the full depth of the case. The important front IO panel features modern connectivity with four USB Type-A (5 Gbps) ports and two Type-C (20 Gbps) ports – effectively like having a USB hub built into the top of your case. There are also three buttons just below the USB ports. On the right are the power and reset buttons; in the middle is a status (power) indicator light; and on the left is the RGB light switch. It’s a sleek design and includes all the functionality expected from a new high-end chassis.

Internal Features

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Inside the case is where the real fun begins. The Cosmos Alpha supports the full range of motherboard sizes, from Mini-ITX to E-ATX/EEB. It’s also rear-connect motherboard/BTF-compatible, which can really clean up the wires. Inside, you can install up to 12 fans (a 4-fan hub with RGB support included) in typical locations (front/side/top/rear), or 4 radiators (up to 420mm on the side). To fit four radiators, three can be mounted on the back, behind the motherboard, with the fourth on top. You can cool anything with that much space available for fans and radiators. Additionally, you can mount your power supply at the top or bottom, where it is hidden from view.

On the motherboard tray, there are removable panels on the right to hide cables, or you can remove them to install additional fans and create space behind the motherboard tray to store wires. You don’t have to move a thing, as there’s roughly two inches (53mm) of space between the motherboard tray and decorative panel. As you'd expect, given the case's size, there are plenty of places to route the wires and mounting points, with velcro straps to keep things neat. Another panel hides most of the wires, so neat routing isn’t terribly important if you don't want to worry about that. But if you’re anything like me, you will group and route the cables using the tie downs.

Compared to how some previous Cosmos cases could hold up to 18 drives, the three available (confirmed by Cooler Master) on the Alpha feel a bit paltry. We realize M.2-based storage has become increasingly popular, reducing the need for most internal SATA-based storage (specifically HDDs), but we’d wager there are some niche buyers looking for more than that in a full-tower case. You can likely print some for it, as there is room and files for generic mounts/rails exist.

You’ll find movable crossbars for fans in front, at the top, and at the bottom, and oval slots for screws/mounting let you install different-sized fans and adjust their locations to reduce hot spots or just fine-tune placement. Moving the crossbars was easy, but the sliding mechanism didn't feel as smooth as I expected/wanted. It's a minor complaint, but this is an expensive case.

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The motherboard panel moves back and forth to increase clearance for, say, large air coolers versus AIOs, mounting fans or radiators behind it, or just to tweak airflow. You can also bring it closer to the side panel to show off your GPU and create more room behind the motherboard. Just be careful, as you can see from our mock build, the GPU can get very close to the smoked-glass side panel, which isn't great for the graphics card's cooling. The chassis supports vertical GPU mounting, but the hardware is not included ($69.99 at Amazon) on the Cosmos Alpha.

Cooler Master also includes an adjustable crossmember that runs from front to back, designed to support large graphics cards. On this bar is a movable support bracket that slides under the GPU to prevent GPU sag and bending.

Bottom Line

The new Cosmos Alpha ($399.99 on Newegg) builds on two decades of Cosmos legacy, modernizing the case with a sleek, solid redesign. The FreeForm 2.0 platform offers greater modularity and personalization, and Cooler Master promises access to open-source 3D files to design your own parts.

The unique sliding fan brackets and a movable motherboard tray are standout features that enable flexible layouts and more configurable cooling. While its size allows for a wide variety of motherboard types, radiators (up to 4), and fan support (up to 12), the case can be cumbersome due to the large footprint and weight. And SATA drive capacity feels limited for the size. Still, the update looks great, uses fast modern IO, and will host the biggest, most power-hungry hardware, along with the fans to cool it. It certainly isn’t cheap, but it could last through multiple builds.

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