One of the more remarkable events in the history of personal computers was IBM contemplating basing their PC on Atari technology. That this was seriously considered, everyone agrees, but it's hard to pin down specifics. Some versions include:
http://www.360doc.com/content/12/0124/10/28217_181627497.shtml
At first, IBM thought about rebranding an existing computer, and had selected the Atari 800. However, after a visit to Atari headquarters, where IBM businessmen were literally put in a box and run through the assembly line by unorthodox and sometimes stoned Atari employees, the computing giant decided they would rather build their own computer.
So that version suggests the deal would have gone ahead but for the difference in corporate culture, which admittedly was large.
https://www.thoughtco.com/history-of-the-ibm-pc-1991408
At one point, IBM considered buying the fledgling game company Atari to commandeer Atari's early line of personal computers. However, IBM decided to stick with making their own personal computer line and developed a brand new operating system to go with.
That version suggests they would have outright bought the company, which is not what they did with Microsoft or offered to do with Digital Research. (Also, I don't think I would call Atari still a fledgling company at that stage.)
https://arstechnica.com/gadgets/2017/06/ibm-pc-history-part-1/
The machine that would become known as the real IBM PC begins, of all places, at Atari. Apparently feeling their oats in the wake of the Atari VCS' sudden Space Invaders-driven explosion in popularity and the release of its own first PCs, the Atari 400 and 800, they made a proposal to IBM's chairman Frank Cary in July of 1980: if IBM wished to have a PC of its own, Atari would deign to build it for them.
Far from being the hidebound mainframer that he’s often portrayed as, Cary was actually something of a champion of small systems—even if "small systems" in the context of IBM often meant something quite different from what it meant to the outside world. Cary turned the proposal over to IBM's Director of (data) Entry Systems, Bill Lowe, based out of Boca Raton, Florida. Lowe in turn took it to IBM's management committee, who pronounced it "the dumbest thing we've ever heard of." (Indeed, IBM and Atari make about the oddest couple imaginable.)
That version suggests the proposal was initiated by Atari, and that it was not in fact seriously considered by the people who would have had to sign off on the deal. It doesn't say why, but the tone suggests corporate culture is a likely reason.
None of these versions points out that a 40-column computer would be unsuitable for business computing in the first place.
I would love to know exactly what happened. Who was in favor of the proposal, and who turned it down? What exactly would it have consisted of; purchase of the company, technology license or something else? An Atari 800 with an IBM badge, or an IBM PC with some Atari technology in the guts, or something in between? How close did it get? What were the stumbling blocks? Why didn't they go to Apple or Commodore, whose technology and corporate culture would both have been closer matches?
Are any more detailed and authoritative sources known to exist?