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[nextpage title=”Introduction”]

Cosmos S (internally called RC-1100 by Cooler Master) is a big full-tower case featuring aluminum body, ten 5.25” bays, a big 200-mm side fan and several other features. Let’s take an in-depth on this new case from Cooler Master.

This case comes inside a big bag, which surely protects it against scratches during transportation, as you can see in Figure 1.

Cooler Master Cosmos SFigure 1: Cosmos S comes inside a big bag.

On Figures 2 and 3 you have an overall look from this case.

Cooler Master Cosmos SFigure 2: Cooler Master Cosmos S case.

Cooler Master Cosmos SFigure 3: Cooler Master Cosmos S case.

In Figure 4, you can see the front panel from this case. As you can see, this case has ten 5.25” bays (three of them are used by the hard disk drive cage, so you have only six of them available; we will talk about this in details later). For removing the bay covers for installing 5.25” devices you need to open the latches available on the sides of the front panel.

Cooler Master Cosmos SFigure 4: Front panel.

Cooler Master Cosmos SFigure 5: Frontal panel with its latches opened.

[nextpage title=”Introduction (Cont’d)”]

This case has one 120 mm fan on its top panel and it has room for you to install two more fans there if you want to. The top panel cover can be removed by unscrewing one thumbscrew available on the rear panel.

Cooler Master Cosmos SFigure 6: Top panel.

Cooler Master Cosmos SFigure 7: Top panel with its cover removed.

The panel containing USB ports and audio jacks is located on the top panel of this case and what is different here from other cases is that its cover uses a touch-activated motorized mechanism (you need to install an adapter on the main motherboard power connector to use this mechanism). This panel is flawless, as it has four USB ports, one FireWire port, one eSATA port, mic in and headphones jacks.

Cooler Master Cosmos SFigure 8: Connectors available on the top panel.

In Figure 9, you can see the bottom panel from this case. As you can see it has a washable dust filter there, located in front of an optional bottom 120 mm fan which doesn’t come with this case (more about this in the next page). The ventilation roles located on the left side of Figure 9 are for the power supply and this case has another washable dust filter there, accessible from inside the case (we will show this filter in the next page).

Cooler Master Cosmos SFigure 9: Bottom panel.

Finally we have the rear panel in Figure 10. On this case the power supply is located on the bottom part of the case instead of the top part. On the top part there are two holes for water-cooling systems and you can also see a rear 120 mm fan which comes with the case. This case has seven expansion slots like all traditional ATX cases. On the top part of the rear panel you can see two levers, one at each side. By pressing these levers you open the side panels.

Cooler Master Cosmos SFigure 10: Rear panel.

Let’s see how Cosmos S looks like inside.

[nextpage title=”Inside Cosmos S”]

As briefly mentioned, this case comes with a big 200-mm fan on its left panel (i.e., the panel you remove to build your PC), shown in Figure 11. All fans from this case uses a three-pin connector and come with a standard peripheral power plug adapter attached for you to install them directly on any standard peripheral power plug coming from the power supply. If your motherboard has enough fan power connectors available please remove these adapters and install the fans directly on the motherboard, because by doing so you will be able to monitor the speed of each fan through your favorite monitoring program. None of the fans have speed control, which is one of the flaws of this case, especially when you think that there are cheaper cases with this feature (from Antec, for example).

Cooler Master Cosmos SFigure 11: Big side 200-mm fan.

In Figure 12 you have an overall look inside Cosmos S. Even though you can also remove the right panel (the one behind the motherboard tray) the motherboard tray is permanently attached to the case, which in this case isn’t a problem, as the case is big enough for you to easily fit the motherboard inside the case. This case comes with a paper attached to the motherboard tray explaining the use of all holes present there. Pay attention as this paper must be removed before you install your motherboard. If you leave this paper it will prevent the correct cooling of your motherboard, as it will obstruct the airflow between your motherboard and the motherboard tray. Pay also attention to the body of the case, which is made of aluminum.

Cooler Master Cosmos SFigure 12: Inside Cosmos S case.

In Figure 12 you can also see the rear and the top 120 mm fans and in Figure 13 we have a close-up of the rear fan.

Cooler Master Cosmos SFigure 13: Rear 120 mm fan.

[nextpage title=”Inside Cosmos S (Cont’d)”]

As we already mentioned you can install up to two additional 120 mm fans on the top of the case (Figure 14) and one additional 120 mm fan on the bottom of the case (Figure 15). As you could see on page two there is a washable dust filter in front of this bottom spot. This case comes with a front 120 mm fan attached to the hard disk drive cage and we will show this fan later.

Cooler Master Cosmos SFigure 14: Top 120 mm fan and place for installing two additional 120 mm fans.

Cooler Master Cosmos SFigure 15: Place for installing a bottom 120 mm fan.

As already explained on this case the power supply is installed on the bottom of the case and there is a washable dust filter below the power supply installation spot. Because of the unusual position for the power supply, this case comes with an extender cable for the EPS12V connector, in the case the EPS12V cable from your power supply shows to be too short.

Cooler Master Cosmos SFigure 16: Power supply installation spot and its dust filter.

One good thing about this case is that it uses thumbscrews to fasten the daughterboards to the case.

Cooler Master Cosmos SFigure 17: Daughter boards are fastened to the case using thumbscrews.

[nextpage title=”The Disk Drive Bays”]

This case has ten 5.25” bays, coming with a removable hard disk drive cage for four hard drives that takes  three of these 5.25” bays (the front 120 mm fan is attached to this cage). The case also comes with adapters to convert any of the 5.25” bays into a 3.5” bay for installing a hard disk drive or a floppy disk drive. The 5.25” bays use a screwless mechanism to hold 5.25” devices, the HDD cage and the adapter, but you still need to use screws to fasten the hard disk drives to the cage or the floppy disk drive (or fifth hard disk drive) to the adapter.

So there are several possible disk drive configurations for this case. The standard configuration will give you four internal 3.5” bays for hard disk drives and seven 5.25” bays. If you use the adapter to install a floppy disk drive or an additional hard disk drive then you will have six 5.25” bays.

If you remove the HDD cage you will have all ten 5.25” bays available, but this is an unrealistic scenario, as all computers need at least one hard disk drive. If you really need a lot of 5.25” bays, then you can remove the HDD cage and install just one hard drive using the adapter, allowing nine 5.25” bays to be available (the problem here is that this case comes only with eight screwless mechanisms for 5.25” devices, so the ninth device would need to be manually screwed).

The big question is: who needs that many 5.25” bays? We think that Cosmos S would be a far better product if it included a second HDD cage. This would expand the number of internal 3.5” bays for hard disk drives to eight (or nine, if you use the extra adapter), giving you four (or three, if the adapter is used) 5.25” bays, which is more than enough even for a hardcore user.

Maybe Cooler Master did this thinking of users willing to install one of their water-cooling systems that use 5.25” bays. In any circumstance, these users could simply remove the extra cage if they needed more 5.25” bays and, at the same time, provide more internal 3.5” bays for the users that need to install more hard disk drives.

Cooler Master Cosmos SFigure 18: Hard disk drive cage.

Cooler Master Cosmos SFigure 19: Hard disk drive cage outside the case.

Cooler Master Cosmos SFigure 20: Hard disk drive cage outside the case.

To remove the hard disk drive cage you will need to remove four screws, two at each side of the cage. 

The hard disk drive cage is attached to the case using one aluminum plate at each side of the cage and the cage has four rubber rings to absorb the natural vibration produced by the hard disk drives (as they use motors that are spinning all the time). The problem is that each hard disk drive is attached to the cage without any rubber ring, a feature present on some cases that are cheaper than Cosmos S. We’d like to see this feature on Cosmos S, which is a very expensive case. Another problem with this case is that it isn’t really “tool less” as Cooler Master claims; you still need to use screws to fasten the hard disk drives to the cage. The screwless mechanisms are only used with 5.25” devices and also to hold the hard disk drive cage to the case.

You can not only remove the hard disk drive cage from the case to facilitate the installation of hard disk drives, but you can also reinstall it anywhere you want. It comes installed on the lower three 5.25” bays, but in Figure 21 we moved it to the middle three 5.25” bays.

Cooler Master Cosmos SFigure 21: Hard disk drive cage on a different position.

[nextpage title=”Installing Optical and Floppy Disk Drives”]

To install optical or floppy disk drives you will need first to remove the meshed cover that is in front of the bay that you want to use. As we already explained, to remove these covers you need to first open the two long side latches present on the front panel.

Cooler Master Cosmos SFigure 22: 5.25” bay cover.

If you are installing a floppy disk drive, you will need to first install the two metallic adapters that come with the case on the drive.

Cooler Master Cosmos SFigure 23: Adaptors for installing a floppy disk drive or a fifth hard disk drive.

The screwless mechanisms for installing 5.25” devices are really easy to use. They have a button that pressed once locks the drive into place. To release the drive, just press the button one more time.

Cooler Master Cosmos SFigure 24: Sliding an optical drive in a 5.25” bay.

Cooler Master Cosmos SFigure 25: Align the optical drive with the other covers or devices.

Cooler Master Cosmos SFigure 26: Fastening the optical drive to the case.

[nextpage title=”Main Specifications”]Cosmos S case main specs include:

  • Application: Extended ATX and smaller form factors derived from this one.
  • Material: Aluminum body and side panels with some reinforcing structures in zinc-coated steel (SECC).
  • Power supply required: Doesn’t come with the product.
  • Available colors: Black.
  • Side panel: Solid.
  • Dimensions: 23 35/64” x 10 15/32” x 24 23/32” (59.8 cm x 26.6 cm x 62.8 cm) (H x W x D).
  • Net Weight: 30.4 lbs (13.8 Kg)
  • Gross Weight: 39.2 lbs (17.8 Kg)
  • Bays: Ten external 5.25” bays with one hard disk drive cage for four hard disk drives and one adapter for another hard disk drive or a floppy disk drive.
  • Expansion slots: Seven.
  • Fans: One 200-mm fan on the side panel rotating at 900 rpm, one 120 mm fan on the rear, one 120 mm fan on the top and one 120 mm fan on the front (glows blue when turned on), attached to the hard disk drive cage, all rotating at 1,200 rpm.
  • More Information: https://www.coolermaster.com
  • Average price in the US*: USD 240.00.

* Researched at Shopping.com on the day we published this review.


[nextpage title=”Conclusions”]

Using aluminum body and side panels, the construction quality of this case is impressive providing a very sturdy looks. We liked the upper handles, which facilitates a lot the transportation of your computer, especially if you have tons of parts inside, which make the computer very heavy. The feet that are actually handles identical to the top handles is also an excellent feature for the same reason. Its size and fans will surely keep you computer running very cool.

Another highlight of this product is the number of connectors (four USB ports, one FireWire port, one eSATA port and mic in and headphones jacks), protected by a motor mechanism activated by touch.

The main problem with this case is its cost: USD 240, on average, in the USA. This heavy price tag keeps this product away from Average Joe. Unless you are just a rich kid buying a case just to show it off to your friends you will need to think twice before buying this case even if you have the money, because it isn’t a perfect product and if you are a savvy enthusiast you may want to take a look at a different case if you are not comfortable with the limitations of this case.

These limitations include:

  • Absence of speed control for the fans (don’t forget to remove the power adapters that come attached to the fans and connect them directly to the motherboard for monitoring the speed of the fans through your favorite monitoring program).
  • Even though the number of fans is more than enough, it could have come with more fans (in particular the bottom fan) especially because of its price.
  • Even though four hard disk drive bays are more than enough for 99% of users, this case could have come with one more hard disk drive cage, which would expand the amount of hard disk drive bays to eight – and this second cage could be easily removed by users that wouldn’t need it. After all, this case is mainly targeted to high-end enthusiasts, and is not uncommon for this kind of user to have more than four hard disk drives.
  • It is not a 100% tool less case, as its screwless mechanisms are only for 5.25” devices; you still need to use regular screws to install hard disk drives to the case.
  • It doesn’t come with individual rubber rings for each hard drive screw, which would reduce the noise produced by each drive.

Of course we wouldn’t be picky about these limitations on a USD 50 product, but if we are paying USD 240 on a case, we want to have a “flawless” product – what, unfortunately, isn’t the case of Cosmos S.

Cosmos S is a good case, don’t get us wrong. We only think it is too expensive for what it brings.