The Mellori ITX case was designed to fill the need for a small form factor for AMD-based systems and measures just 195x190x60mm high (plus feet). The mellori achieves this small size by combining several existing innovations. First the AMD Raven Ridge CPUs have integrated graphics, allowing the system to omit a bulky graphics card to reduce overall height. The back panel space where such a card would go is used for the power connector and button. Next, by using the Minibox PicoPSU power supply, a whole lot of space is saved while moving the bulk of the supply to a brick outside the PC. Hard disk space is reduced by using an SSD. Finally, by lowering the top of the case below the height of the CPU cooling fan, that fan serves double duty. It cools all components while providing an aethetically pleasing feature on an otherwise non-descript small box. Air vents are on the bottom and force air past key components before exiting.
The top design is motherboard specific but easily adapted. The files here are specific to the Gigabyte AB350N Gamng WiFi motherboard. For more complete instructions and adaptation to other boards check out the GIT repository: https://github.com/phkahler/mellori_ITX
Only the bottom requires support, and only for the 4 hex shaped holes for the nuts. There is a test piece with this geometry so you can try different support options quickly.