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Define XL, Black Pearl Case, USB3
(1 review)
Define XL, Titanium Grey Case, USB3
(3 reviews)

Fractal Design Define XL Computer Cases


Now available in Xtra Large, the Define sets new standards in PC case technology. Quietness, tidy internals and quality construction - this case has it all!

As the name implies, Define XL is the larger sibling of the acclaimed and award winning Define R2/R3 case. It is similar to the Define R2/R3, and offers a number of interesting functions with a very stylish appearance. It is a case focused on low noise level, without neglecting other important features such as cooling, expandability and ease of use.


  1. Stylish design
  2. Pre-fitted with noise absorbing material
  3. Configurable thermal chamber design
  4. Great cooling possibilities, 3x fans included (2x 140mm, 1x 180mm)
  5. 10x HDD slots
  6. Unique ModuVent™ design in side panel

The XL is pre-fitted with dense noise absorbing bitumen material, covered with a soft foam texture. This material effectively absorbs noise generated by the components and fans inside. Paired with other noise preventing features such as a covered top panel with a 180mm fan mounted at an angle to blow out air in the rear and silicone grommets for hard drive mounting, the XL truly excels in delivering a low noise solution.

An important feature of the XL is the division into three thermal chamber designs. This enables the user to freely choose the best thermal configuration suited for their needs.

1. The upper main chamber, contains most of the components, such as motherboard, ODD and one HDD cage. This main chamber is cooled by one 140mm fan in the front (included), one 120mm fan in the front (optional), one 140mm fan in the rear (included), one 120 or 140mm fan in the side panel (optional) and one 180mm fan in the top (included). The top 180mm fan is mounted at an angle, blowing out hot air through the rear side of the case. As mentioned earlier, the top cover has a clear acoustic advantage in that it prevents noise being emitted from the top of the case.

2. The second thermal chamber (PSU chamber) is connected to the main chamber with a removable lid. Due to the lid being removable, it is possible to turn the PSU upside down which will then expel air from within the main chamber. Alternatively the PSU can be installed with the fan facing the bottom of the case. Air is then brought into the PSU from underneath the case through the supplied air filter.

3. The third chamber is the lower HDD chamber, consisting of room for six hard drives. This chamber is cooled by an optional 140mm fan at the front. By default the air flows over the HDDs and therefore becomes warm. It then exits the system behind the right side panel (seen from the front) and out of the rear of the case. However, the user can decide to remove the dividing metal panel between the lower HDD chamber and the PSU chamber, to let the air flow over the PSU and out of the rear ventilation holes.

Another unique feature with the XL is the ModuVent™, inherited from the Define R2/R3 case. This is a cover fitted with noise absorbing material, mounted in the side panel fan aperture, allowing the user to choose between an optimal low noise level, having the cover mounted or optimal airflow by removing the cover and mounting a fan for air intake.

Image showing the possible install positions for main chamber HDDs
Image showing the possible install positions for main chamber HDDs

Apart from all these features, XL also offers excellent cable routing possibilities, with large holes and enough space for cables behind the motherboard plate. The cable routing holes are lined with silicone covers, effectively hiding the cable clutter.

Also supplied is a fan controller. This uses a spare expansion slot at the rear of the case. It is capable of controlling up to three fans with one dial.

Image showing top 180mm and side 140mm cooling fans
Image showing top 180mm and side 140mm cooling fans

SpecificationsDefine XL BlackDefine XL Grey
Dimensions232 x 560 x 561.3mm
Weight17.95 Kg
Motherboard CompatibilityMini ITX, Micro ATX, ATX and E-ATX
Power Supply CompatibilityStandard ATX, can accommodate long PSUs
PCI/AGP Card CompatibilityFull size, any length
3.5" Drive Bays10, all SSD compatible
5.25" Drive Bays4, one bay converts to 3.5" for floppy or card reader
Roof Cooling Fans1x 180mm fan (supplied)
Rear/Side Cooling FansSide 1x 120 or 140mm side fan (not supplied), Rear 1x 140mm rear fan (supplied)
Front/Floor Cooling FansFront 2x 140mm fan (one supplied), 1x 120mm fan (not supplied)
Expansion Card Slots7, with sleek white painted brackets
Front I/O Ports2x USB 2.0, 2x USB 3.0 and Audio I/O
AccessoriesPCI fan controller, controllers up to 3 fans
Warranty24 months
EAN barcode7350041080480 7350041080497

Customer Reviews

Define XL Black
Define XL Grey

Brilliant case


This is a really nice case, well worth the wait! A few thing to consider are its weight and size, with my computer inside it weighs about 25kg and just about fits under my desk. You might want to get some extra long cables as well, it's pretty annoying when your sata power connector won't reach the dvd drive.

The front panel has a nice feeling when you open it, like opening a refrigerator door. Nothing feels bendy, all the panels are flat and quite thick, just waiting for some ram to arrive before I boot up and see how noisy (or quiet) it is.

Awesome... tombstone


These are the first two words my wife said, watching Define XL Titanium standing near our last case (CM Sileo 500). Monolithic, classic, stunning design, that please your eyes and ears with perfect view and real silence. "Seek and ye shall find", you know, and there's one the most perfect cases for any home PC: gaming or HTPC. 10 well-cooling HDD (or SSD, if you need 10 SSD's ^^), air-filters for all input fans including filter for PSU, great sound isolation, lot of place inside case for easy installation (even for internal water-cooling system with thick rads!) and easy breath with silent fans: three 140 mm (supports 2 of them) and one - 180 mm. Cold, stylish, silent... Ideal!

From Russia with love to Quiet PC! Thanks a lot for quick delivery and excellent product!

Very Quiet, Bad Packaging


I wanted a quiet case, this is very quiet, I'd say quieter than the Mac Pro cases, and with less intrusive noise (low frequency air flow only). I've an Intel 1155 board with I5, Noctua twin fan cooler, with one fan installed, it draws air over a 8400GS silent video card then over the processor fins and straight out of the top fan. Temps are: Processor 24-30c (highest temp I've yet achieved, GPU 35-42c. Brilliant, but I don't do games. The case is big, heavy, and the packaging is inadequate for bone-headed couriers so both ones I ordered arrived smashed. One was from a site sounding like the well known auction site, and it was a bit of a shambles, but this one came from QuietPC and they sorted the troubles out easily, quickly, and courteously. I will definitely use them again.



I have 2 of these cases. I am very happy with there solid construction. This design is well thought out. Remember to buy extra long 24pin and 8pin power cables or extensions.


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