The Cooler Master N400 Chassis

Cooler Master is well known for manufacturing cases that suit all types of users.  While the majority of their recent cases have been geared towards gamers and enthusiasts, they recently announced new line of cases, the “N” series.  This new line incorporates features commonly found with enthusiast cases; however it has a very minimalistic feel to it.  Currently there are three cases making up the “N” line, the N200, N400 and N600.

Cooler Master N400 PC Case

Today, we will be taking a look at the middle of the series case, the N400.  This mid-tower case sells for $50.92 shipped, under the part number NSE-400-KKN2-AMZ.  This is a very low cost mid-tower case.  While cost can sometimes be an indicator of quality, Cooler Master’s reputation should also be taken into consideration.  For this price, you are receiving a solid-black case that includes many features such as USB 3.0, water cooling compatibility, support for high-end graphics cards (up to 320mm/12.6 inches) and plenty of storage options.  In addition, Cooler Master provides a 2 year warranty with the N400 case.


While most systems implement water cooling on the back, top, front or bottom areas of the case, Cooler Master has placed a water cooling or fan mount on the back side panel.  Here either two 140mm fans can be installed, or up to a 240mm water cooling radiator.


SSD’s are one of the hottest storage options which can provide a good performance boost to most systems.  Cooler Master has provided the capability of installing three 2.5” SSD’s in the N400 (without needing additional hardware).

Cooler Master N400 Key Features:

Let’s take a look at the packaging and accessories that came with our review sample.

N400 Retail Packaging

CM N400 Case Box

As a mid-tower case, measuring 7.5x16.7x19.7 inches (WxHxD), the packaging is approximately 9.5X19x22.5 (WxHxD) and a shipping weight of close to 15lbs.  The packaging is pretty plain, and the front provides a minimal amount of information with the model name, front panel view and a few high level features.

CM N400 Case Box

The back of the box goes into more detail with a view of the interior.  Here the features are pointed out in plenty of detail, with enough information provided for the average user to know what the N600 is capable of.

CM N400 Case Box side

One side of the box has a detailed list of the specifications, which includes a detailed list of the cooling options.  The other side of the box provides a view of the front and side panel.

CM N400 Case Box package

Opening the box, the N600 is packaged in a plastic bag, nestled between two large Styrofoam blocks; this is a very common method of packing cases.  The plastic bag will protect against moisture, while the Styrofoam blocks provide protection against minor damage.


As with any good case, a number of accessories are included.  This includes a large number of drive and motherboard screws, nine motherboard standoffs (with an installation bit), standoff screws, two sets of fan screws, power supply screws, side panel security bracket with screws, motherboard speaker, cable ties and a detailed installation guide.  Two of the standoffs are designed to help align the motherboard by going into the screw holes.

N400 External Impressions


Taking a look at the front bezel, there isn’t too much here that should surprise anybody.  There are two 5.25” drive bays, and one 3.5” drive bay.  The entire front bezel is a wire mesh, which should help with airflow.  On the right side of the front bezel we have the usual buttons and I/O ports; reset, power, headphone, microphone, 2 USB 2.0 and 2 SuperSpeed USB 3.0 ports.

CM N400 Bezel Removed

Removing the bezel is accomplished by pulling from the bottom.  Behind the bezel the 5.25” and 3.5” drive bays are revealed.  Below the 3.5” bay is the two 120mm fan mounts (one is included).  On the bezel, the drive bay covers are held in place by simple push clips.  The entire bezel is covered in a fabric mesh to act as a filter.

CM N400 Side Panel

The left side panel is plain, except for place to mount a fan.  Here either a 120mm or 140mm fan can be mounted, which should put it over the video card.

CM N400 Back Panel

The back panel looks like most other mid-tower cases, directly above the motherboard I/O port key is an included 120mm fan.  Next is the seven expansion ports, and two external water cooling holes.  Finally, the important power supply hole.

CM N400 Back side Panel

Usually the right side panel has nothing to be concerned about, however, Cooler Master has designed the N400 with the ability to install two 120mm fans, or a 240mm liquid cooler.  Either way, airflow is necessary, so there is a wire mesh area for the necessary airflow.


Two 120mm fans can also be installed in the top panel.  These fans, along with the other possible locations should provide plenty of airflow inside the case.


On the bottom of the case there are the standard four feet to raise the case.  In addition, there are four holes for the screws to mount the 2.5” drive at the bottom of the 3.5” drive chamber.  Finally, there is a filtered vent for the power supply.

N400 Internal Impressions

CM N400 Inside

Taking the side panel off, and taking a look at the painted interior, a few things immediately jumped out.  The motherboard tray is sunken in, with the standoffs the motherboard will be at the same height as the rest of the motherboard tray.  For each of the drive bays, which could be used tool-lessly, however Cooler Master includes tool-less brackets for the 5.25”, external 3.5” and two of the 3.5” drive bays.  This leaves a potential for 5 other 3.5” hard drives to be installed with screws.  A large hole in the motherboard tray provides ample access to the back of the motherboard, easing installation of CPU coolers.  There is also one additional hole for cable routing.

CM N400 Inside Back Panel

The back panel of the case, we find the usual suspects, an exhaust fan, motherboard I/O key, seven expansion slots, two external water cooling holes and a power supply slot.  The included exhaust fan has a standard fan power cable, along with a Molex power adapter.  The expansion port covers are attached to the case, once these are removed there are no additional covers to replace them.

CM N400 Inside Top Panel

Looking at the top panel, we find the included filter.  It is not easily removed for cleaning or even allows for easy installation of a water cooling radiator or two 120mm fans. 

CM N400 Inside PSU Mount

The view of the power supply area, shows the metal mesh Integrated filter, like the top filter, it can’t be easily removed to be cleaned; the power supply will need to be removed to fully clean the filter.  Cooler Master did take into account the vibration a power supply creates and installed some rubber anti-vibration feet to help with that.

CM N400 backside

Normally, the back side the motherboard tray has nothing too exciting to see.  However, as Cooler Master has decided to use the space behind the 3.5” drive chassis to install two additional 120mm fans, or water cooling radiator, it’s an important side to see.  In addition, there is the tool-less 2.5” drive chassis which is removable. 


A close-up view of the rear cooling options shows the tight quarters.  Unfortunately, the 2.5” drive chassis uses the fan mounting screw holes.  It appears that only one fan can be installed if you want to use the 2.5” drive chassis.


The tool-less 2.5” tray can be removed for installation.  Each of the drives can slide into the bracket and is held in place by a simple lock.  While the drives can be installed in either direction, depending on the drive the locking mechanism might not work properly unless installed with the data connections towards the middle of the chassis.


Since fans can be installed in the back side of the chassis, Cooler Master has once again included a filter try keeping your case dust free.  Like the other filters, it is not easily removed without taking the back panel off.

CM N400 Hardware Installation

CM N400 Case With Hardware

After installing all the components, we can see that everything fits without too much issue.  Obviously cable management needs to be a little tidier, however without any holes in the motherboard try to route the cables behind the tray that will be a bit tricky.  Moving the hard drives down a slot or two allows for plenty of room for long video cards.  Let’s take a brief look at what it took to get the install completed.

CM N400 Case With Hardware

At the bottom of the 3.5” drive chamber there is a place to install a 2.5” hard drive.  The screws go through the bottom of the case.  Here the drive is resting on the bottom of the case so the data and power connector needs to have straight connectors.  Placing a Raptor drive here might cause some vibration, including some raised feet with rubber might be a good idea in case somebody does this rather than installing a SSD (where vibration won’t be a concern).

CM N400 Case With SSD

Sliding 2.5” drives into the removable tray to be hidden in the back is a nice advantage.

CM N400 Case With SSD

However, if you install two drives, it’s likely the data and power connectors will be next to each other causing some conflict, using two right angle data connectors won’t be possible, however straight connectors will work fine.


Thanks to the two tool-less brackets, installing 3.5” hard drives is easy.  Remove the brackets, place the drives in place, and reinstall the retaining brackets.  Only enough brackets for two hard drives are included, using more than 2 3.5” hard drives you’ll have to use screws.


Installing the 2.5” SSD tray in the back location, you do lose one of the places to install a fan.  However, one additional fan can still be installed. 


Finally, should a change in the CPU cooler be necessary, the hole in the motherboard tray is sufficient to allow plenty of access to the back of the motherboard.  This keeps from having to remove the motherboard to upgrade the CPU cooler.

Final Thoughts and Conclusions

The Cooler Master N400 has many options to cool your components, ranging from simple 120mm or 140mm fans to installing 120mm or 240mm water blocks.  The overall design of the N400 is very simplistic, while still looking like a more expensive case with just enough flash for it to look great.


While there are areas of concern with the N400, we also have to keep in mind the cost of the case, for $50.92 shipped on Amazon, you are getting a well-built case, with 2 SuperSpeed USB 3.0 ports, water cooling compatibility, fully painted interior and a 2 year warranty at a very low price point.


The entire front bezel of the case has taken airflow into consideration using a honeycomb patter on the front bezel, with very little plastic.  In addition, the capability of installing multiple water coolers can allow the system to be nearly silent.  The N400 also has an external 3.5” bay, which can come in handy if a small card reader or additional USB 3.0 ports are desired.

While there are plenty of cooling options available, Cooler Master has included filters to help keep the system clean.  It would be nice to be able to remove these filters for cleaning, however that might increase the cost.  The power supply filter would be the first on my list to get an upgrade.

As for installation, it went pretty smoothly.  Everything slid into place as it should without any major issues.  If the user decides to install CPU water cooling, this is easily accomplished as the back of the motherboard is easily accessed.  While a fairly short video card was used in the build, a longer video card, up to 12.6 inches, will have plenty of room.


For me, the biggest headache was cable management, as there are no holes in the motherboard tray to allow the cables to be hid, they are all visible after the build is complete.  The side panel doesn’t have a window so for the average user, they will be hidden after the system is built.

Overall, there are no major issues with this case.  For those wanting a great case at a budget price the N400 would be a great option.


Legit Reviews Value Award

Legit Bottom Line:  Cooler Master’s N400 is a budget friendly mid-tower case that offers compatibility with advanced features.