For height and depth its a little less than a mid-tower, its just wider. Think about it, they only need room on the left side for the motherboard, anything that attaches by PCIe and a CPU cooler, so it doesnt have to be tall enough to fit a PSU below the mobo, and it doesnt have to be deep enough to fit storage or optical drives infront of the mobo, all of that stuff is in the section behind the motherboard. Basically its not that much larger than the motherboard, it just needs room for the cable routing from the back.