Fractal Design Define S Case Review

Designed for liquid-cooling enthusiasts, Fractal Design’s Define S could be the perfect solution for your next extreme cooling build.

Early Verdict

The Define S is solid and attractive enough to hold an “Ultimate Liquid Cooling” build. Unfortunately, it’s not designed to hold “Ultimate Performance” parts such as 10.5” to 10.7” deep motherboards or four-way SLI that might need an “Ultimate Liquid Cooling” configuration. “Extreme” builders able to live within the confines of standard ATX and seven expansion slots will find equally extreme value in its low $70 price.

Pros

  • +

    Thick, well-fitting steel panels

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    five hidden drive trays

  • +

    support for two triple-fan radiators

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    superbly low price

Cons

  • -

    No eighth expansion slot

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    no space for oversized motherboards

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Specifications, Interior & Exterior

“Extreme” system builders are known for chopping away at their cases to fit more stuff inside, typically ditching entire drive cages and sealing off external bays in order to create more mounting space and a “cleaner” look. Fractal Design takes the concept a step further by eliminating those parts from the entire design of its Define S, while maintaining the sturdy shell upon which the company has built its reputation among some of these same enthusiasts.

The best part might be that Fractal Design isn’t charging you to modify an existing case, but has instead deducted the cost of bays and cages from the price of a new model. Weighing in at a fairly hefty 18.2 pounds even without the weight of cages, the Define S sells for around $70.

Specifications

Exterior

Before we open the Define S to reveal its variety of internal liquid cooling support features, let’s take a closer look around the outside.

Fractal Design replaced its classic noise-dampened door with a similar-looking solid face panel, above which are two USB 3.0 ports, power and reset buttons, plus headphone and microphone jacks. Removable outer covers behind those ports allow full access to the internal top panel.

Because it’s designed for lots of internal liquid cooling hardware, Fractal Design saw no need to put port holes for liquid coolers on the back of the Define S. We don’t consider that a weakness, though we would have preferred to see eight expansion slots rather than the seven provided.

A magnetic front and slide-in bottom dust cover protect all “intake” positions, including one optional bottom fan mount, three front fan mounts, and a power supply inlet.

Interior

Other than its durable steel sheetwork, Fractal Design is also known for its liberal application of cloth-faced asphalt damping sheets. The Define S’ plethora of vents combine with its left side window to leave only the right panel with enough space for proper application of these sheets. This may not be the most effective location to focus its noise-reduction efforts, but it is the most practical.

Inside, we find a front panel support for triple-120mm radiators (we refuse to call these 360mm because they’re 120mm wide), in addition to wider dual-140mm units (280x140mm spacing).

There’s around 17.8” of card space as well, which gets reduced by the thickness of any fans and/or radiators added to the front panel. That doesn’t mean we can install an oversized motherboard, though, as the raised section at the front of the motherboard tray limits internal board depth to around 9.9”.

A look around the back of the tray shows why motherboard length is restricted to standard ATX: three 3.5” drive trays fill the forward edge of the “stow” space, and two more 2.5” trays rest directly behind the board. The larger trays are also dual-drilled for smaller units, in case you’re inclined towards five 2.5” drives.

The lack of front drive cages gave Fractal a lot of room to place screw holes and slots for various liquid cooling devices.

Fractal Design defines the Define S as having room for a “420mm” radiator, but it’s hard to see how the tanks of some 3x 140mm units will clear the case ends. Triple 120 is far easier, and both sets of mounting screws are offset away from the motherboard to allow vertical overlap without component collision.


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Thomas Soderstrom
Thomas Soderstrom is a Senior Staff Editor at Tom's Hardware US. He tests and reviews cases, cooling, memory and motherboards.
  • basroil
    This is no Define model... they basically took out everything that makes the Define R cases so good (noise suppression, good cooling, tons of disk space, etc)
    Reply
  • redgarl
    I have a Define R2 XL and I must admit that if you use the 3.25 bay for your drives, you get the same results as here.

    I love my case, but my next case will be a Phantekk.
    Reply
  • Crashman
    16780643 said:
    This is no Define model... they basically took out everything that makes the Define R cases so good (noise suppression, good cooling, tons of disk space, etc)
    It still has the sheet of asphalt on the back panel, and that sheet of asphalt still has a cloth facing. Same piece as before. The window of this model prevents Fractal Design from using it on the other side, but the firm also sells a non-windowed version with asphalt sheet on both sides.

    Reply
  • ingtar33
    The Define S is pretty much identical to the R5. all they took out of the define r5 (to turn it into the S) was the front mounted drive mounts, and did a little tinkering with the back motherboard tray, creating more room then normally would be found in a define r5/r4

    I've owned a number of Fractal Design cases, the S is just a commercial version of a standard case mod done to the R5. Fractal Design learned that water cooling enthusiasts were buying their R5, and removing all the drive cages, including the dvd drives to fit large (>240mm) sized radiators into the case. So they decided there was a market for a slighly modified version of the r5 in the water cooling enthusiast community.

    As a sidenote, I've owned the R4, R5 and Arc Midi. In all 3 (though only one was water cooled) i stripped out the front drive cages because the weakness of a FD case is how badly those drive cages (even when not used) destroy case airflow. Whether i was using water or not, after removing those drive bays i have seen a consistent 5C drop in temps across the board. So for my money, the Define S is an improvement on their very good R4/R5 and Arc Midi cases.
    Reply
  • ingtar33
    if only FD would sell their cases with fans less noisy then a dump truck. the one universal problem i've had with FD cases has been the god awful case fans they come with.
    Reply
  • stoned_ritual
    if only FD would sell their cases with fans less noisy then a dump truck. the one universal problem i've had with FD cases has been the god awful case fans they come with.

    Wow! I never had any problems with their fans. I have owned 3 fractal cases (define mini, node 304 and 804)
    Reply
  • eklipz330
    they should make a case like this that focuses more on air cooling.

    also, how many ssd's can you fit?
    Reply
  • RedJaron
    That may be the first time I've heard someone complain about FD fans being loud.
    Reply
  • cgigoux
    Now if only they would carry these design changes into the Define Mini (which they haven't redesigned since it was introduced!). Having room behind the MoBo tray for 2 x 2.5 & 2 x 3.5 drives would create the potential for a potent SFF gaming system.
    Reply
  • atheus
    16782687 said:
    Now if only they would carry these design changes into the Define Mini (which they haven't redesigned since it was introduced!). Having room behind the MoBo tray for 2 x 2.5 & 2 x 3.5 drives would create the potential for a potent SFF gaming system.
    I'm impatiently waiting for an updated Mini too. They have a survey up on the front page of their site which seems to be collecting opinions for a new mATX case. With any luck that's the overdue mini update they're polling for.

    To the fellow saying Fractal Design fans are loud, you either got bad fans, or you mistook noise from some other fan in your case. The FD fans don't even have a high max RPM, so it just doesn't make sense that they would be even slightly loud, much less "noisy as a dump truck".
    Reply