I mean, such AI tools know absolutely nothing about your board, yet they don’t know how to respond “I don’t know”, they’re trained to respond whatever but to respond. You can never trust their knowledge. See them as the annoying coworker who constantly brags and speaks loud to impress others but sometimes knows a thing or two. They’re similar. Just try them by asking facts about stuff you know well (e.g. your employer: who runs the company etc) and you’ll observe a terrifying mixture of some valid elements and total garbage. Use them to translate text, get cooking recipes or suggestions to then fact-check on a search engine, or to solve simple problems, but not to get facts, because that’s what they’re terribly bad at. That was my point.
I don’t read German but apparently it’s made for Rock 5B so it should be OK. In my case, I used a 4x4x4cm one with long fins and it’s sufficient. Ah I found the link to the photo I posted. The difficulty is to fix a heat sink that was not designed for a given board, of course. Oh by the way, if you end up with a self-made solution, be careful about the solution you use to attach the heat sink. In the past on other boards I’ve used silicon glue that’s made exactly for this, and regretted it: the glue is super strong, and when trying to pull the heat sink off, the SoC’s lid came with it. Some thermal pads are sticky enough to hold a heat sink in place. Or you can find some thermal thin double-sided sticking tape that works relatively well. But better use the vendor’s solution.
It can be a matter of brand or quality, or generation since prices are falling.
Be careful about one thing regarding multi-output power supplies: they’re often made for charging devices, and often when you connect a new port, during the power negotiation, they cut the power to other ports then re-enable it a second or two later. That’s not a problem when charging, but it’s extremely annoying when used to power an SBC. I’ve seen this with all USB-PD power supplies till now. My rock5b has been rebooting every time I plugged or unplugged my laptop from the PSU. So I’d advise you to be careful if you want to power multiple boards from the same power block.
It’s just marketing to make people buy new adapters they already have. It’s just that the technology is evolving and vendors figured it was better to stick a version on them. Look here for example. In short its “good”, “better”, “even better”…
But Arm is being used in all Macs since the M1, in Snapdragon-based Lenovo laptops, SoftIron’s Overdrive 1000 featuring AMD’s Opteron A1100, various boards such as SolidRun’s Honeycomb using NXP’s LX2K 16-core chip, Ampere Altra-based Gigabyte/Asrock/Supermicro boards that are both for servers and high-end workstations, and of course Radxa’s Rock5 ITX and Orion-O6 boards.
Essentially development and testing. I’m luck enough to receive some early samples from Radxa because apparently I torture them enough to help spot limitations that can be improved in the final model 
. But in practice they’re already perfectly good when I receive them so I keep them for development. I installed my Rock5 ITX in an enclosure and connected 4 SATA SSDs and a 10G NIC to it, planning to replace my file server, but never felt brave enough to definitely switch to it, because for me data are extremely precious and I tend not to change something which works. But eventually I will do. The O6 is nice for experimenting with AI on CPU. It is as powerful as a 2-3 year old x86 laptop with good memory bandwidth. It draws a little bit too much power (about 11W idle) but is overall a great board for various use cases including development. I even bought a second one .