Mainstream PCs these days can easily fit into smaller and smaller form factors, but truly high-end builds with the latest many-core processors and massive AMD or Nvidia graphics cards aren't quite able to take advantage of the miniaturization trend. Cooling those chips and feeding them with massive amounts of storage capacity still demands massive cases, and actually building such a system can reveal unforeseen speed bumps even in cases that seem perfectly poised to accommodate high-end hardware.For just one example, when I put together our Ryzen Threadripper video-editing build earlier this year, mounting our 360-mm radiator in the top of that case required me to collapse the Fractal Design Define R6's many 3.5" bays into just two behind-the-motherboard mounting points.