The air and water show
As a basis for comparison, we're going to include the stock cooler that comes with recent Phenom II processors.

AMD's stock cooler has a couple of heatpipes, but it's otherwise quite different from the Kingwin and Noctua towers. Most significantly, the AMD cooler's airflow runs perpendicular rather than parallel to the motherboard. The low-profile, nine-blade fan is also smaller and thinner than the 92 and 120 mm units on the other air coolers. The stock cooler's fan will have to spin much faster to move the same volume of air as the towers. The good news is that the cooler's small size will fit into a much broader range of enclosures, including smaller Micro ATX designs.

A copper base forms the foundation of AMD's Phenom cooler. Two pairs of heatpipes are embedded halfway into the copper base before looping upward to transfer heat away from the core. Almost 60 aluminum fins stretch between the base and the fan.

If you've been reading our case reviews, you're already familiar with the test rig we use to see how well enclosures handle the heat put out by a modern PC. In this round-up, we're using mostly the same gear to push a Phenom II X4 940 on an Asus M3A32 MVP Deluxe motherboard. Based on which allowed for the higher overclock in each scenario, I've used either two sticks of DDR2 memory from A-Data or two modules of Corsair CM2X1024 RAM. In testing, I was able to hit higher clock speeds on most of the units with a higher multiplier but lower base clock. The opposite proved true for the Noctua, and since the Corsair RAM seemed to handle the higher base clock better, I used it instead. An XFX GeForce 8800 GTS 512 graphics card and Enermax MODU82+ 625W PSU rounded out the test system, which was wrapped in a Thermaltake Spedo enclosure.