The Cooler Master ATCS 840 Full Tower Classic Case constitutes a classic all-aluminum design that builds on the legacy of the original ATCS design. The aluminum construction not only allows for a lighter weight but complements the thermal design seamlessly with three 230mm fans, dedicated air duct for graphics card cooling and HDD cooling module for superb cooling.

Extra attention was paid to make sure this elegantly designed chassis is not only easy to install but easy to maintain. This includes: slide-out motherboard tray along with cut out CPU access for easy removal, tool-free HDD casing, patented finger pressing 5.25" drive. Lastly, it gives users the freedom to choose any components they desire, as it supports the latest standards such as E-ATX and dual PSUs.

We just took the case and added a HUGE window to the side and bolted that bad boy on! Now you can have all the performance gains of the Cosmos and the looks of a large windowed side panel.

Download Manual

Features

• Elegant extruded aluminum bezel with CM nameplate
• Concealable I/O panel with brushed plate
• PCI-Slot meshed brackets for extra ventilation
• Meshed ventilation hole to provide a passive cooling
• Meshed top panel design for maximum ventilation
• PSU can be mounted on the top or bottom for a dual PSU system
• Removable HDD racks with anti-vibration pads for easy assembly and reduced noise
• Retaining holes for best cable routing and neatness
• Meshed top panel design for maximum ventilation
• Removable Motherboard tray sliding on the ball bearing drawer

Cooling System

• Dual 230mm top fans provide for improved exhaust airflow
• Dual or triple 120mm radiator can be mounted inside the top of the casing (radiator is optional)
• HDD module with dual 120mm LED to enhance internal airflow
• Independent air intake designed for bottom-mounted PSU
• Extra-added 120mm fan can be installed on the bottom pull cool air from the bottom of the case
• External air duct to updrade cooling for your graphics cards

Model:	RC-840-KKN1-GP (Black)
Color:	Black
Dimension:	9.57 x 22.83 x 24.80 in. (W x H x D)
Motherboards:	Micro-ATX ATX E-ATX
5.25" Drive Bays:	6 x External (without use of 5.25" to 3.5" bay converter)
3.5" Drive Bays:	6 x Internal 1 x External (using 5.25" to 3.5" bay converter)
I/O Panel:	4x USB 1 x IEEE 1394a (Firewire) 1 x eSATA 1 x Mic 1 x Audio
Expansion Slots:	7
Cooling System
Front:	1 x 230x30mm fan 700 RPM, 19 dBA (included)
Top:	2 x 230x30mm fans 700 RPM, 19dBA (included) (can be swapped for three 120mm fans)
Rear:	1 x 120x25mm fan 1200 RPM, 17 dBA (included)
Bottom:	1 x 120mm fan hole
HDD Module:	2 x 120mm fan holes
External Air Duct:	1 x 120mm fan (optional)
Power Supplies:	2 x Standard ATX PS2 / EPS 12V

10-24-2009
Reviewer: chem light (2)
The case is beautifully designed with plenty of room, a removable mother board tray, very silent fans moving lots of air, and the window mod is done well. To give you an idea of big this thing is, I have an EGVA Classified mobo in this thing with a GeoForce GTX 285 video card and it barely looks like there''s anything in there.

08-06-2009
Reviewer: clevlandrockz (1)
As everyone says, CAVERNOUS. A full ATX motherboard looks like a mini in this case. Gonna have the inside coated. My only complaint on this case is that the retaining clips for the front bezel covering the fan are plastic and does not hold it very solid. These should be spring steel. Coolermaster has been very slow in replying to me about replacing them, it keeps falling off.

08-04-2009
Reviewer: swage99 (1)
coolmaster-ATCS-840 fulltower case is a totally AWESOME CASE! makes the best computer server, lot of room! best computer you every buy!

05-17-2009
Reviewer: Crispex (2)
I originally received a normal CM ATCS840 without a window, but within a day FrozenCPU had the problem sorted out and the correct side panel shipped to me. They did a very fine job on the window, a very nearly perfect mod. Be warned, having this mod done to your case may warp the side panel very slightly, but it makes no difference. If you want to be able to show off the inner components of your case, that shiny new graphics card or water-cooling setup, this is the way to go. The panel I received was clear enough to make people who didn''t know it was a window think that the case was open. Good job, you guys at Frozen. Keep it up!

02-12-2009
Reviewer: Froggled (1)
Had this case since earlier this morning, been a complete joy to work with. The premodded window is very professional and very clean, much better than my own hackjob on my last case. The case is extremely large, by far the largest full tower I''ve ever worked with, tall wide and deep. I''m pretty sure I could fit a small child inside, might have to hack off a few limbs... The case itself is beautiful, plenty of upgrade room. It was shipped out within a day and got here in just a couple more. Great stuff. :)