ATCS (Active Thermal Convention System) series of cases is not new in Cooler Master’s product portfolio. In 1999, Cooler Master was one of the first manufacturers that launched chassis made completely of aluminum. Models ATC-100, ATC-200 and ATC-300 were mid-tower and full-tower models based on ATCS concept while ATC-400 was rack-mounted model.  These models had good (in their own time) stock cooling solution, compared to similar models from that time. Good fan organization combined with natural attributes of aluminum guarantied good cooling performances to ATCS series. ATCS 840 model went few steps further and set new standards in this product category.


Design

ATCS 840 is full-tower chassis with respectable dimensions: 243x583x630mm. With dimensions like these, good ventilation and cooling properties are guaranteed. Although it’s not nice to discuss about design and tastes we can say with certain confidence that this is universally nice chassis. Simple design with slightly rounded edges in combination with brushed aluminum surface creates elegant looks. ATCS 840 is manufactured in two colors: black and silver (aluminum).

On front side are placed six 5.25inch bays for devices like optical devices or HDD racks. Last bay can be converted to 3.5inch format thanks to supplied converter. Mounting of 5.25inch device is simple without need to use screwdriver or screws. It is enough to press button on the side and device will be locked in its position. On bottom part of front side is mounted aluminum plate that protects filters. Someone will dislike its looks and good news is that it can be dismounted and modified according to personal taste. Behind this aluminum plate is air filter that can be dismounted, thanks to plastic mounting clips, to clean it up. When air filter is removed, it reveals 230mm fan that is responsible for air intake. Besides huge air flow, this fan is characterized by low noise levels. It is certified on 19dBA at 700rpm. This fan has also function of cooling HDD cage that is mounted behind it. HDD cage is rotated for 90 degrees so mounting and dismounting of hard disks is easy. It is enough to place HDD into plastic drawer and place it into one of 6 bays. This nice and elegant solution also lowers HDD vibration. On the left side of the HDD cage are 2 mounting places for 120mm fans that in combination with 230mm fan in front can create push&pull effect that always results in perfect HDD cooling. Beside first air filter at front, there is one more filter on the bottom side where can be mounted another 120mm fan. Place for main power supply unit is at the bottom. We found this position to be better than usual location (at the top of chassis). We say main power supply unit because this chassis allows you to mount another (secondary) PSU at the top. This solution can be useful for servers, powerful workstations or users that need to provide separate power supply unit for some components (CPUs, HDDs, graphics cards etc).

In case you decide to mount secondary power supply unit you will need to dismount two 230mm fans that are mounted on top side of chassis and are used to take out hot air from inside of chassis. These fans are protected by aluminum mesh at the top and this mesh can be also dismounted without use of any tool. If you plan to use water cooling system this chassis supports even that. There are holes for hoses at top. Left and right sides of this chassis are identical and they have no openings for fans or ventilation because this chassis actually doesn’t need those. On top side closer to front is nicely designed front panel with push&popup mechanism. Front panel has all necessary connectors: eSATA, 4xUSB, IEEE1374 Firewire, mic and headphone connector. In front of retractable front panel, closer to front edge of top side, are located power and reset buttons along with signaling diodes. This solution is so practical and nicely designed that we have to wonder why no one until now came to similar idea. We hope that in the future we will see more chassis front panels designed in this manner.