I finally did it. To save power and to replace my Laptop after almost 10 years, I've bought the Mele Quieter 3Q Mini-PC for approx $329. I chose the version 8GB RAM / 256GB eMMC.
On the device there is a preloaded Windows 11 Pro (shiver me timbers), which I booted, made updates (insane CPU load and takes forever. Windows...), checked the device specs, and turned it off to install an Intenso 500GB premium NVMe 2280 SSD. Then, with a preloaded USB stick, I installed Ubuntu 22.04 on it.
Everything runs great so far. Device speed is great with the Celeron N5105. The 8GB RAM is directly soldered to the board, which is a bit unfortunate. No way of easily upgrading to 16GB. But whatever...
Heat was the big question. Since it's fanless, that was a major concern for me. I "overcool" devices usually to get most lifespan out of it. But my concerns seemed to be a bit high. The temperature never reached 80°C. But to keep my mind at ease, I put a heatsink on top of the device (which itself functions as a heatsink) and underneath it. Totally unnecessary but now temperatures of the CPU never rose over 62°C and the SSD chills at 32°C.
For me, the most important part was the power consumption:
Ubuntu 22.04 on internal Intenso 500GB NVMe 2280 SSD
Idle: 4.1 Watt
Video 1080p: 7.7 Watt
Video 4k: 12 Watt
Max: 14 Watt
This is awesome and even lower than my Raspberry Pi 4 with a Sata-SSD on idling and video playback. Of course the max possible power intake is higher than the Pi. But I'm impressed to get these numbers with higher performance.
Of course it's much lower than my old laptop with 8.3 Watt idling, video 1080p at 18 Watt and max at 28 Watt.
It's fun to use and was no hassle to install. You can boot from internal eMMC, internal NVMe SSD and from an external drive such as an USB stick or harddisk. I didn't try the microSD card slot for booting.
It's so tiny, it uses no space on the desk, and there are a plate for VESA mounts to put it behind your display.
All in all it exceeded my expectations. Admittedly those weren't set too high. My old i3-3120M was easily tripled by benchmarks and it feels much faster. Don't try to play hardcore games on it. But it can run great emulation software and casual modern games without problems.
There is one thing that is strange though. On Ubuntu 22.04 playing 4k video is no fun. Horrible framedrops, and sometimes even a complete stop of playing occurs (leepsvideo hdr test video e.g.). This could be the drivers from Ubuntu, since it does not happen on Windows 11 Pro. At 56°C, so no throttling or overheating. I'll have to dive into this later.