Actually the short history of the playstation is this. Nintendo was working with Sony to create a CD-based add-on for the Super Nintendo. Near the finalization of the add-on, which was called PSX for Play Station Experimental (hence the abbreviation for anybody who was wondering), Nintendo realized that Sony would gain a large degree of control despite their leading position in the video game market. Nintendo then went to Phillips and that's when the CD-i thing came out. The basically betrayed Sony in a business sense and Sony was thinking of halting their research but decided to make it a complete, stand alone console.

You can read the development of it here: PS Development but it doesn't mention anything about it being called PSX. I'm pretty sure that it was though, cause I read about that a while ago on a completely different site, and wikipedia doesn't necessarily have all the information proper.

-Shark2k