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Cooler Master Cosmos II review: Cooler Master Cosmos II

The Cosmos II is big and beautiful. You'll need to put aside AU$369 and a lot of floor space — but, if you can afford both, you'll never regret it.

Craig Simms Special to CNET News
Craig was sucked into the endless vortex of tech at an early age, only to be spat back out babbling things like "phase-locked-loop crystal oscillators!". Mostly this receives a pat on the head from the listener, followed closely by a question about what laptop they should buy.
Craig Simms
5 min read

There are words. Big. Huge. Gigantic. Behemoth. World enveloping.


Cooler Master Cosmos II

The Good

Huge and beautifully designed. Swing-out doors that can also be detached. Lots of opportunities for cooling and cable management. More drive bays than most people have drives. Potential to sink through the earth due to pure size.

The Bad

5.25-inch drive bay release buttons don't seem very reliable. Some fans in our test sample clattered. Hot-swap drive bays are connected together and permanently connected to cables. Fan controller isn't very accessible. 3.5-inch drive bay locking mechanism is more flimsy than we'd like.

The Bottom Line

The Cosmos II is big and beautiful. You'll need to put aside AU$369 and a lot of floor space — but, if you can afford both, you'll never regret it.

Able to take up to XL-ATX boards, the Cosmos II is all of these things. With reinforced handles that could be used to bench press the chassis, Cooler Master's flagship case is the supercar of PC cases. Totally unnecessary, but utterly drool worthy.

A soft-sliding, high-friction panel at the top reveals a power button and buttons that cycle fan speeds across multiple areas of the case. In our testing, the front fan's speed could not be changed, nor could the LED be turned off.

Mmm, buttons.
(Credit: Craig Simms/CNET)

You can get access to the fan controller underneath by popping the top panel behind it, removing two screws and cutting a couple of cable ties, but it's hardly worth it; many of the plugs are glued down. You're better off getting a third-party controller for one of the 5.25-inch bays if you plan to expand your cooling. Below the touch-button panel is an IO panel with headphone and microphone jacks, two USB 3.0 ports, four USB 2.0 ports and an eSATA port.

You can fit up to three 120mm fans at the top — decent for water cooling radiators. The fan controller hides underneath the top section, which can be removed via two screws.
(Credit: Craig Simms/CNET)

Another panel at the front slides down to reveal three quick 5.25-inch removable drive bay covers, the bays behind which can lock in a drive with the press of a button. Our top bay button tended to get stuck, which prevented us from easily inserting a drive. Removing a drive was a pain, too, as you couldn't tell whether the push button had been pressed in or not, short of trying to physically remove the drive.

We'd love the 5.25-inch lock buttons to be more reliable, and also to indicate whether they've been locked or not more clearly.
(Credit: Craig Simms/CNET)

Your hard-drive options are plentiful, and each tool-less bay can hold either 2.5- or 3.5-inch drives.
(Credit: Craig Simms/CNET)

Two hot-swappable, lockable 3.5-inch bays sit below the 5.25-inch section, although these can be removed to give you another two 5.25-inch bays. Both the 3.5-inch bays have non-detachable SATA and power cables, though; a pain if you haven't filled the bay or need longer cabling. It's going to be a pain if you just want to remove one, too, as the two bays are riveted together rather than screwed in.

The SATA and power cables are fixed to the hot-swap bays. An odd choice for an enthusiast chassis.
(Credit: Craig Simms/CNET)

Opening the case is a delight, with both sides hinged at the front and opening like car doors, and released by independent latches at the rear. If you feel like you need more room, the doors can easily be lifted off their hinges and removed.

Two latches on the rear release the side doors.
(Credit: Craig Simms/CNET)

Inside, you're greeted by an absolute mess of cables for the front IO panel, quick-swap hard drives and the included fans, with the latter terminating in a three-pin connector. There's also a huge wad of two-pin connectors that are used to control the lights in LED fans, but you'll mostly want to tuck these away, out of sight.

Good thing there's plenty of cable-management space and pass-throughs.
(Credit: Craig Simms/CNET)

A 140mm fan sits at the rear, a 120mm fan at the top, a pair of 120mm fans at the bottom and a big, 200mm LED fan at the front, with the front panel of the case easily detaching to reveal it. Cooling expansion is also plentiful: there's space under the 200mm fan for another 120mm fan; the top of the case can either house an additional two 120mm fans, two 140mm fans or a single 200mm fan; and the top can be accessed by removing a single cool to play with water-cooling radiator mounts. Three water-cooling pipe pass-throughs are situated above the rear extraction fan.

The 200mm LED fan is tucked away in front of the drive bays.
(Credit: Craig Simms/CNET)

Five quick-removable, screwless 3.5-inch drive bays are under the 5.25-inch drive-bay stack and cooled by the 200mm fan, which can mount both 2.5- and 3.5-inch drives. Another six are under this, hidden behind dual 120mm fans that extract directly outside thanks to filtered grilles in the case sides. The closing latches on these drive bays are a little more flimsy than we'd like, but they still fulfil their purpose.

More drive bays behind a pair of 120mm fans.
(Credit: Craig Simms/CNET)

The doors are solid, with removable panels at the bottom so you can clean the dust filters. The motherboard side door has a mounting spot for two 120mm fans, positioned to approximately where your expansion cards are. If your video card or something else runs hot, this could be a welcome addition.

More fans can be added to one of the doors.
(Credit: Craig Simms/CNET)

Being the huge size that it is, the rear features 10 PCI brackets, with one more vertical one next to them, so things like port extenders for motherboards don't interfere with valuable PCI-E slots.

The tray itself features a hole for quick access to your heatsink, and large, plentiful pass-through holes are available, so you can cable as neatly as you like. The power supply sits in a physically separate section, with only pass-through holes available for the power cables. As is all the rage, a removable filter sits underneath, where the PSU goes, and vents its air. As a nice touch, the PSU mount is padded so that the power supply doesn't scratch.

A padded PSU mount minimises scratches.
(Credit: Craig Simms/CNET)

Building simply isn't an issue, thanks to the pure size of the case. Accessories include the usual screws and standoffs, the keys for the quick-swap drive bays, cable ties (both stand-alone and ones with an adhesive base) and an extended eight-pin power cable — perfect for those boards that annoyingly place the connector too close to the CPU socket, leading it to be obstructed by large coolers.

Disappointing, though, are the fans — specifically, the quietness or lack thereof. On our test sample, the rear and hard-drive fans made a clattering noise no matter what speed we set on the front panel. With everything closed up and running, we're quite sure it'll be fine for most, but for those with sensitive hearing it's likely to irritate.

These are a given, right?
(Credit: Craig Simms/CNET)

The Cosmos II is big and beautiful. You'll need to put aside AU$369 and a lot of floor space — but, if you can afford both, you'll never regret it.