Cooler Master Cosmos II review: Cooler Master Cosmos II

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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.

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8.5 Overall

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

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.