A new take on the low-noise mid-tower

A premium low-noise case with a hinged glass side panel

CORSAIR's Carbide Series has a new low-noise option in the 678C, a mid-tower enclosure with internal sound damping panels and full tempered glass side panel. Convenience features include the hinge and magnetic closure of the glass side panel, along with a hinged front panel that opens to reveal the front fans and corresponding screen filter – and a rare 5.25-inch bay which allows for installation of an optical drive for those of us who still use discs (this author included).

So does the Carbide 678C provide a compelling mix of features in the premium segment of the case market, and provide real competition for the Define R6 from Fractal Design against which it will be inevitably compared? Let's find out.

Features for the Carbide Series 678C from CORSAIR:

  • Sophisticated Style: Defined by clean lines and smooth steel construction, with a crystal-clear tempered glass side panel to show off your system’s components.
  • Extensive Sound Damping: Sound damping material on the side, front and roof panels ensure quiet operation – or swap in the included dust filter on the roof when performance is your top priority.
  • A Multitude of Cooling Options: Includes space for 360mm push/pull radiators in the front and roof, 280/240mm radiators on the floor, and 140/120mm radiators in the rear.
  • Massive Cooling Potential: Powerful and efficient airflow, with room to install up to 9x 120mm or 7x 140mm fans for massive cooling potential.
  • Take Command of Your Cooling: A PWM fan controller regulates three included SP140 PWM fans and up to three more. Reduce fan speed when you want keep your system quiet, or increase when you want to push its performance.
  • High-Speed USB 3.1 Gen-2 Type-C Port: Front panel connector puts future-proof connectivity within easy reach.
  • Expand Your Storage Options: Install up to 6x 3.5in and 3x 2.5in drives. A versatile HDD/ODD design includes six modular trays that can be moved to eight mounting locations to give you the exact layout you want.
  • Easy Accessibility: Both the front panel and tempered glass side panel are hinged for tool-free easy access.

The insulated front door opens to provide access to the fan filter and 5.25-inch drive bay


  • Material: Steel, Tempered Glass
  • Form Factor: Mid-Tower
  • Expansion Slots: 7+2 vertical
  • Drive Bays: 6x 3.5-inch, 3x 2.5-inch
  • Radiator Compatibility: 120mm, 140mm, 240mm, 280mm, 360mm, 420mm
    • Compatible Corsair Liquid Coolers: H55, H60, H75, H80i, H90, H100i, H105, H110i, H115i, H150i
  • Component Clearance:
    • Maximum GPU Length 370 mm
    • Maximum PSU Length 225 mm
    • Maximum CPU Cooler Height 170 mm
  • Case Dimensions: 549 x 239 x 497 mm (21.61 x 9.41 x 19.57 inches)
  • Weight: 13.056 kg (28.784 lbs)
  • Warranty: Two years

Launch price and availability: $199.99, Amazon.com

Case Exterior

There's nothing flashy here, as CORSAIR has gone with a minimalist approach totally devoid of RGBs (just one blue light on the upper right corner when the case is powered on).

The front panel has a brushed finish to the plastic, hiding the optical bay an front fan intake. Both this and the side panels are hinged and close with magnets, making access to the interior as convenient as possible.

The side panel has a fairly dark tint to it, but component lighting – if you go down the road of motherboard/memory/cooler/graphics card RGB – will still be visible, if a little muted.

Case I/O is up on the top right, and includes a basic compliment of USB and 3.5 mm audio.

The top of the case can provide further noise reduction via an included insulated panel, or better airflow with its magnetically attached mesh panel.

Around back we see the standard ATX mid-tower layout with the additional 2x expansion slots for a vertical GPU installation alongside.

The bottom of the case offers a full screen filter, and this conveniently slides out from the front for easy access.

And finally a look at the included hardware, and the screws are individually bagged which is always appreciated.

Interior and Build Notes

The component chamber offers grommeted cable openings to the right of the motherboard tray, with additional open routing spaces above and below the motherboard.

At the rear of the case interior is one of the three pre-installed 140 mm (SP140 PWM) fans.

Looking to the right we can see four of the included hard drive trays which protrude into the component chamber (the empty space for another pair allows for the installation of longer graphics cards). Another of the included SP140 PWM fans is installed on the front intake, which can be accessed from the front with the fan filter removed.

The bottom of the case interior offers another grommeted cable opening, and is well ventilated.

Around back we ee a left side dominated by 3.5-inch hard drive bays (8 bays total, 6 trays included), and three of Corsair's spring-loaded 2.5-inch bays are positioned below the motherboard cutout.

Above the cutout you may notice the PWM fan hub, which connects to an available motherboard fan header to allow for customizing the speed of up to six fans.

The rear panel offers noise insulation to match the material found inside the front panel and optional top panel.

As to the build, one of the first things I did was check the fit of an optical drive:

Drives of more recent (compact) vintage fit without protruding from the 5.25-inch cage, and while longer drives fit as well they can obstruct liquid coolers at the top of the case.

A 280 mm liquid cooler (CORSAIR H115i) fits up on the top of the case with just enough clearance around it, though installation was a little tight with the optical bay in place.

This optical bay can be removed, which would allow for installation of up to 360 mm radiators with supporting fan mounts on the top of the case.

Looking next to storage, the included hard drive trays come out with three thumbscrews apiece, and the drive mounts are insulated with soft rubber to reduce vibration.

As mentioned there are a total of 8 openings for 3.5-inch hard drives, with 6 of the trays included. Of these the lowest two are hidden behind the PSU shroud.

It's worth noting that no bay covers are included should you wish to remove any of the upper hard drive mounts within the component chamber.

SSDs installation is completely tool-free, with a spring-loaded mount for up to three drives (these release by pressing a tab to the top of each slot).

The rest of the build process is as straightforward is possible, with no clearance issues or other problems to report.

Completed Build

The finished build with an ATX motherboard and standard-length graphics card fits neatly into left side of the case, which would allow for up to up to six hard drives to be installed on the other side.

Around back space for cable organization is at a premium, and it will require some additional care to rout things around drive bays and get the back cover into place. A little more room back here would have been welcome, considering the thickness of the insulation on the rear panel. Still, I did get the panel on without any bulging and the finished build looked great.

Temps and Noise

PC Perspective Enclosure Test Platform
Processor Intel Core i7-8700K
Graphics Card NVIDIA GeForce RTX 2080 Founders Edition
Storage CORSAIR Neutron XTi 480GB SSD
Power Supply CORSAIR RM1000x 1000W
CPU Cooler Cooler Master Hyper 212 RGB Black Edition
Operating System Windows 10 64-bit

Performance numbers were very good, and cooling was actually a lot better than expected even with the solid top panel in place (this is how we tested it). Air is drawn in from underside of the solid front panel and also from the bottom of the case, and here the vented shroud beneath the motherboard tray helps promote airflow quite a bit.

At first blush it appears that there just isn't sufficient airflow for this design to work, but it does. Don't be thrown by the lack of visible front intake as the cooling performance is just fine – and again, that's with the solid top panel in place.

Noise levels were also quite low, staying south of 35 dBA with loads closer to 33 dBA. The tested air cooler – a Cooler Master Hyper 212 RGB Black Edition we recently reviewed – was silenced very effectively as it reached nearly 40 dBA on the open test bench and was barely registering over 33 dBA inside the case. Likewise the tested RTX 2080 barely registered over the nominal ~32.6 dBA idle noise from the three included fans, and in general the noise levels are excellent.


The Carbide Series 678C is a quiet mid-tower case with a good build quality, a sleek and understated look, and good performance. Its $199 launch price does place it $50 above the similar-looking Fractal Design Define R6, but in fairness to the Carbide 678C there are some significant differences with CORSAIR's design here which are improvements, such as the hinged tempered glass panel, more robust 3.5-inch drive trays, and the three spring loaded SSD mounts. Do these differences make up the disparity in pricing? To some extent, yes, but $199 does feel high and a lower price point would make this case much easier to recommend.