Sega Yeno DPH-64 existed?

I think you (@warmize) may have mixed some things up / someone else has mixed things with something?

It seems it was a fact they seemed to mix up some components at the assembly line back in the 1992 . But it was the Sakhr AX-660. So an MSX+Sega (Mega Drive/Genesis) hybrid does exist. I don't recall about Sega or Yeno branded hybrids, or SMS hybrids. But there was the IBM/PC/MSX -hybrid SVI-838 (especially more of a functional hybrid with the SVI-811).

I have a vague memory I may have seen articles about other computers which can run games for MSX and some other console/computer, but I'm not sure...

There's always a possibility some company was about to release a computer (or any other product) but for some reason it was cancelled at the last moment. Sometimes the decision to not release might have been made even after some marketing material was released.

For example, in Finland there almost was a Salora branded MSX (well, more like Salora re-branded/distributed MSX made by Mitsubishi or Toshiba), but it never got beyond prototyping. IIRC there were even some ads/articles in some Finnish magazines!

Perhaps it's the same with this Sega branded MSX? There was some marketing and it was announced, but never actually released.

One reason they might have decided to not release it, could be because they would have been competing with themselves. Sure - the MSX is also a computer suitable for programming and other more general use, and their consoles only suitable for gaming, and by releasing a computer they would be venturing to a bit larger marketing segment - but OTOH someone at the company might have made (the correct) market analysis that most MSXes would used by kids playing (computer) games. Hence: they could be cutting into their own sales.

I'm fairly certain many MSX users from Japan frequent these forums / use this site, and also, if a Sega branded MSX computer existed, it would certainly have some pictures around the net since such a computer would be seriously interesting to any hobbyist/computer/gaming enthusiast interested in the era (MSX is very well known in Japan, and Sega probably worldwide). It would also be mentioned in the Wiki, if it existed.

It's not impossible it exists and has gone under everyone's radar somehow, but very unlikely (more likely if the number ever produced was for some reason very small, well less than 100 units total).

Well, on smspower was a guy who said that he owns a Yeno. So I think this maschines really exist.

That would be a good explanation. Thank you very much!