The most prominent feature of the Accelero Xtreme IV is the array of three 92mm fans which span the top of the cooler. These are configured to blow down towards the PCB, with air passing through the heatsink and out past the PCB underneath.
Turning over the cooler reveals the full extent of the heatsink underneath which is very large indeed. Although it may appear to be a similar length as most high-end graphics cards in pictures, its actually significantly longer, measuring 288mm in length.
Perhaps the most significant measurement in depth, though. The 54mm overall depth means that the cooler effectively takes up three expansion slots. This measurement excludes the backplate heatsink, though, which adds on another 23mm.
So when both of these are installed together the whole card will take up five expansion slots, making a dual graphics card configuration an impossibility. It may cause other compatibility issues with CPU coolers and other components depending on the layout of your motherboard.
Arctic thoughtfully pre-apply the MX-4 thermal paste to the copper CPU block, which feeds the heatsink through the five copper heatpipes.