Cooler Master has always prided themselves on having… well… cool looking shipping containers and the MasterAir MA624 Stealth is no exception. This shipping container is funky cool but may not be everyone’s cup of tea… as purple and black is a rather unusual combination. One that Cooler Master somehow manages to not only make work but work well. Of course, having a such a (visually) loud box for a model dubbed ‘stealth’ is a bit ironic but we really do not have any issue with it. It is covered in details, it will standout on retailer’s shelves and do so without you wanting to gouge out your eyes to make the pain stop.
Thankfully while the exterior of this cardboard box may be a touch controversial to some, the internals are sure to please everyone. In typical Cooler Master OCD fashion, the design team specified a veritable ton of formfitting foam be used… and then separated the fans, the accessories, and the actual cooler from each other (as an aside the cooling tower also has more foam inside its internal cardboard box). Yes, that makes for a grand total of three internal cardboard boxes. Now that is a ‘defense in-depth’ protection strategy that will allow the cooler (at the very least) to survive darn near anything this side of being run over by a fork-lift. Needless to say, you can rest assured that it will survive the tender mercies of your shipping agent… even if they kick it all the way to your home. Color us impressed.
The accessories included are both high quality and rather comprehensive. So comprehensive a few issues are conspicuous by their lack of company. What we mean by this is the accessories that you get are rather impressive. Mounting hardware for everything from ancient Intel 775 to ‘modern’ 2066 to AMD FM1 to AM4 is included… yet sTRX4 (or any ThreadRipper socket for that matter) sadly is not. While we love the fact that Cooler Master includes three fans including a 120mm for increased RAM height compatibility… they only include enough mounting hardware for two fans. While they include a long screwdriver to make mounting the MasterAir MA624 Stealth easy… it barely worked and we spent more time getting it back into the Philips head of the two integral bolts than we did turning said bolts.
This ‘great ideas w/ less than ideal implementations’ is going to be a recurring theme. Thankfully, the underlying design is so bloody powerful and such overkill for consumer sized/grade CPUs that they become more ‘quirks’ than out and out deal-breakers. Furthermore, all the quirks can easily be fixed with very little effort. This too is a recurring theme. One that may make the MasterAir MA624 Stealth a bit too quirky for its asking price.
This however is getting ahead of ourselves. Let’s start with aesthetics. Great Noodley Appendages this cooler is gorgeous. Forget model gorgeous. Forget supermodel gorgeous. Forget perfect 10 out 10. Think super model multiplied by supermodel gorgeous. Think Spinal Tap’s “It goes to 11” gorgeous. Seriously. The combination of super dark / ‘jet’ black fin arrays and heatpipes with nickel plate base just plain works and it will work in darn near all builds. First time. Every time.
Moving on to the fans that are included. In grand total you get three fans. Two 140mm SickleFlow 650-1400RPM Rifle Bearing fans capable of moving (up to) 67 cubic feet of air with 2.25mm of static pressure, and one 120mm SickleFlow 650-1800RPM (also rifle bearing based) fan that moves up to 62cfm at 2.5mm of static pressure. To be blunt these are very good fans and we really have no major issues with them. We typically dislike mix ‘n’ match setups but fully understand that using a 120mm on the outside of a dual tower cooler is a good idea. You may loose a bit of theorical air movement, but in return you get better static pressure (and thus better air movement through the fin array in the real world) and do not need to worry about RAM height (as much).
The downsides to Cooler Masters design with the fans are three-fold. Firstly, if you do use a 120+140 configuration (or 120+140+140 setup… obviously) you should not use the included fan splitter. The differences in speed (and thus static pressure) is just too great. Instead, you should plug each into their separate 4-pin fan header and tune them in your motherboard’s BIOS. This is a common complaint we have with most dual tower coolers and basically falls into ‘water makes things wet, and the sky appears blue’ type deal. It just is something you have to deal with regardless of manufacture if you mix n match fans.
The other two are both directly related to mounting design. Cooler Master wanted to make as ‘cool’ looking a CPU cooling solution as they could and to this end have gone with plastic (with integrated rubber vibration dampeners) mounting hardware that doubles as fan shrouds/fan fascia. We like this two-piece design. What we do not like is that fact that Cooler Master did not include a second one. On a hundred dollar cooling solution. In other words, if you want to use all the fans included in the box you need to grab some wire and make your own ‘old school’ fan clips. This is not a big deal as anyone can do this, it just will mar the final appearance of the MasterAir MA624 Stealth. Cooler Master really needed to include a second set.
The other quirk is the centrally located 140mm fan. If you look at the MasterAir MA624 Stealth side on… you can see fresh air on both the intake and exhaust of it. This is because Cooler Master does not include a central fan shroud. This lack of a shroud means that a certain amount of the 67CFM rating’s worth of fresh air is going to skip the intake side’s fin array… and a certain amount of said air is going to hit the exhaust side fin array and bounce out and around the fin array. While it is true a fan pushing air into or out of a fin array will mostly negate this issue… Cooler Master does not include the hardware to mount a fan on both the intake and exhaust side of the MasterAir MA624 Stealth. Thus air is going to skip a fin array. This inherent lowering of performance plays a big part in why the MasterAir MA624 Stealth does not perform nearly as well as say a Noctua D15 or Phanteks PH-TC14PE.
Thankfully the short-term fix for this quirk is easy. Tape both sides of the central fan to both of the fin arrays. Do that and in testing you will boost the MasterAir MA624 Stealth basically up to Noctua D15 performance levels(ish). The longer-term solution is to 3D Print a custom fascia out of high temp plastic that covers both sides of said fan. Neither should be necessary mods on a hundred dollar cooling solution.
On the positive side… the MasterAir MA624 Stealth’s underlying design is such overkill that it can afford to burn efficiency.
When setup in dual fan mode this monster is over six inchesdeep and is 6.3-inches tall. That is a ton of surface area for cooling the six 6mm integrated heatpipes. Of course not all that area is take up with cooling fins so lets break down how much surface area there really is.
Both fin arrays are mirror images of each other and are 5.5-inches wide with 43 fins per array.
Both are basically 4 inches tall.
Both are about 1.83 inches deep. This gives a theorical 2D ‘face’ area of 44 square inches and about 865.6 inches of surface cooling area. However, both fin arrays have cutouts for RAM (and motherboard VRM heatsink) compatibility.
These cut outs are obviously 5.5inches wide, about 0.65 inches tall and is done to the bottom 7 fins.
They are also about 0.5 inch deep.
Obviously, the face surface area is the same, but it does cut it back from ~865.6 to ~830.1 inches of surface cooling area. Needless to say… that is a loooot of surface area for heat transference from the metal to the air to occur.
In typical Cooler Master cynicism the base of the MasterAir MA624 Stealth is polished to a mirror shine but it is not perfectly flat. Integrated Heat Spreaders on mass produced CPUs are not always perfectly flat and the slight center point in the MA624’s base helps to overcome this unevenness and provide better IHS to cooling base contact. Needless to say… if you plan on lapping your CPU’s IHS lap the base of the MasterAir MA624 Stealth at the same time!
