A fanless mini PC with the power of a modern Ultrabook. The ZBox CI660 proves you can passively cool a 25 W Core i7-8550U CPU without resorting to severe throttling.
https://www.notebookcheck.net/Zotac-ZBOX-CI660-Nano-i7-8550U-Mini-PC-Review.333436.0.html
Still can't find the CI6x0 models for sale at any U.S. online stores.
The zotac quality is crap. I had one that gave random hardware problems since the start, all related to heat I think. Most could be solved by endless restarting, takeing out memory, cooling the device and or removing the power cord for some minutes. Two days ago it suddenly stopped and since then it is completely dead. Nor amazon nor zotac responded to my questions what's next... so I ordered a fan cooled device.