ASRock has introduced the Jupiter X300, its latest mini-PC. The Jupiter X300 is a particularly compact mini-PC based on AMD's X300 chipset. Correspondingly, the Jupiter X300 has an AM4 Socket and supports up to 65 W APUs. Its 1.07-litre case should be small enough for most desks, too.
https://www.notebookcheck.net/ASRock-Jupiter-X300-A-mini-PC-with-a-1-07-litre-case-that-supports-up-to-65-W-AMD-Ryzen-4000G-APUs.517283.0.html