Cooler Master ATCS 840 Full Tower Case Review

Interior Impressions Con’t

Besides improving the shear number of drives the ATCS 840 can hold over the HAF, Cooler Master has also addressed our main concern with dead air zones. Unlike the HAF this drive cage also boasts the ability to mount two 120mm fans on its side. This in a nut shell would make the two fans mounted here suck any and all hot air away from the hard drives, push it towards the motherboard area where it could then be reused to cool other parts (as hard drives don’t exactly run hot these days) and then be expelled out the top of the case. It’s a simple and elegant solution which we were delighted to see.


If there is one area in the whole interior of the ATCS 840 which we are disappointed with it has to be how the 7 peripheral slots are handled. Unlike the wondrous tool-free design used in the HAF this case goes old school. Not only do you need to use screws to secure your daughter cards in place but you also need to stick them outside the case to do it. As we mentioned in a previous section, we are not impressed with this setup and feel this is the Achilles heel of the 840. It really is puzzling why Cooler Master’s engineers felt the need to mess with a system which is already pretty darn good. Messing with and improving a system is one thing, but those self same brilliant engineers broke not just one Cardinal rule of engineering but two: "If ain’t broke don’t fix it" and “If you do fix it, make sure it ends up better than the original one”.


Taking a close look at the fans and reporting on them is extremely easy as there really is only two fans in this case. The first fan is a 120mm fan used in the 840 as the lone rear exhaust fan. This 7 bladed, 120 x 120 x 25 mm sleeve bearing fan (model A12025-12CB-3BN-F1) rotates at a nominal speed of 1200rpm while moving about 44CFM of air. When compared to the HAF’s 140mm fan (which also rotates at 1200rpm) this fan is a bit on the anemic side, moving 13CFM air less.

On the positive side, it is fairly quiet and is fairly vibration free. It is certainly not in the same league as a Noctua NF-P12-1300 or Scythe S-Flex E or D but it is not bad by any stretch of the imagination either. It does exhibit about the same amount of slop as its larger 140mm brethren found in the HAF 932, but it certainly is not the worst fan we have handled either. All in all, it is decent fan which is quiet enough for most people; however, if you are a silent PC enthusiast it will be one of the first things you remove.


The other fan, which just happens to be used THREE times in this case is the CM A23030-10CB-3DN-L1. These 9 bladed, 200 x 230 x 30mm fans are rated at 700rpm. While Cooler Master still has not released any information on these, we are still inclined to believe the 75CFM estimate bandied about on various forums on the net. We are also inclined to believe this fan is a sleeved bearing fan; we believe this is the case as Cooler Master fans with "CB" in model number usually mean sleeved bearing.

On the whole, all three fans are very well mannered and produce very little felt vibrations when running full speed. All three also exhibited very little shaft slop and even though they are a long bladed fan they have surprisingly little off axis slop as well. They may not be as tight as some 120mm fans but pressing down on one of those long blades does product a heck of a lot more torque than doing so on a 120mm fan, so allowances have to be made.


Continuing onto the bottom of this case we come to one of the two mounting locations for the Power Supply Unit (PSU). Technically you can have a dual PSU setup, but just like the HAF 932, this case does NOT come with necessary power adapter to allow powering up secondary PSU when you turn on the computer. For all intents and purposes this is a bottom mounted PSU case which can house the power supply at the top if you are willing to sacrifice cooling to do so.


The area below where your PSU shelf is a filtered intake port to allow your power supply's fan easy access to fresh clean air. This in a nut shell removes the PSU from your cooling equation, but it does mean the fan in the PSU should run slower as it will have a steady supply of ambient temperature fresh air. Everything in life is a trade off but we think this is a darn good one, and actually prefer this design to a more normal “suck the hot air out the back of the case via the PSU fan” method of case cooling.

The only real difference between the ATCS 840’s PSU shelf and the one found in the HAF 932 is this shelf is not adjustable. This may be an issue if your have an overly large PSU but for most owners you certainly will not notice the difference as a regular “full size” PSU is dwarfed by the size of this shelf. As with the HAF 932, there is room in front of the PSU (assuming a normal length PSU is used) to allow mounting a 120mm intake fan. As previously noted, and as with all the other intake fan locations in this case, this one is also filtered so adding a fan here will not result in a large increase of dust accumulation inside the case.


For all you eagle eyed readers out there, the answer is YES, this case has an even bigger cut out for your PSU cables. Actually, calling it a cut out belies the fact that the whole entire length from the back of the case to the motherboard tray’s vertical stop bar is completely open. Please don’t misunderstand us, the motherboard tray area which comes out is above the PSU zone so you do not have to worry about yanking all your cables before you can remove that tray.

The easiest way to think about the PSU zone is that the motherboard tray slides over an empty area where you can stuff your cables; rather than thinking of these holes as some add on or cutout. This idea is further reinforced when you turn the case around and remove the other panel. You can see that Cooler Master has once again taken the time to really think about and then engineer a great cable management system for this case.