With android boxes, there are two performance specs currently out there on the market, that make sense:
1. NVidia Shield
2. This Chromecast with Google TV dongle:
https://www.androidpolice.com/2020/...pcoming-android-tv-dongle-code-named-sabrina/ (respectively the chip thats inside, which also is in other devices)
None of which are sufficient for PS2 emulation.
The sad truth here is, that android boxes are on a regression slope..
My second (?) generation Amazon 4K Android TV box (btw - stay away from amazon boxes, if you cant root them - they are building closed ecosystems, have blacklisted launchers in the past, ...) is more performant than that google chromecast thingy that came out five years later.
The NVidia Shield is stuck on the same spec for over five years now.
Every manufacturer realized, that they only need so much GPU power, and no CPU power, to decode 4K 24 fps, and thats really all those things are sold for.
Which is really, really sad - but sadly the truth.
They are worse, than current generation smartphones. Which might change the earliest, when a Switch pro comes out (Nvidia would then produce those processors at scale - and probably also update their NVidia shield at that point).
--
On the PS2 emulation front - you need about 1.1 TFLOPs of GPU performance - see:
That handheld is using a 4500U Ryzen chip, but also has a graphics card in there. The Ryzen chip alone wouldnt even give you a third of the GPU performance needed.
The GTX 970 I mentioned had about 4 TFLOPs of GPU performance, which was more than enough.
A GTX 950 or 750Ti would be the equivalent at about 1.1 TFLOPs of GPU performance, which is as low as you should go for PS2 emulation.
So thats your GPU target for "how low you could go - buying a (used) gaming PC", and also your answer on - no, a Ryzen APU (what would be in a NUC style device) is not enough for PS2 emulation.
--
Dreamcast is one ARM development cycle away from being able to run on your calculator, so that wont give you many problems (see:
).
And again, the best price performance device to emulate PS2 currently is a Xbox Series S - but you'd have to make sure to be able to get your hands on a non advertised method to install a copy of retroarch from a developer account that Microsoft greenlit for actual public distribution of software. And you arent getting more than hints here at the moment, because people dont want that method to be shut down.
edit: 4500U (What would be in a Ryzen NUC) seems to be enough for some PS2 games - but only at 1x resolution, and not for God of War 2 f.e. - so... not ideal.
edit: Mistake - the handheld above only runs a Ryzen 5 4500U APU, which actually gets 1.1 TFLOPS of GPU performance - which is not enough to run God of War PS2 at full speed.
So maybe eying GTX 970 class GPUs for PS2 emulation isnt such a bad idea after all.