Microsoft co-founder and billionaire Paul Allen tells all about his relationship with Bill Gates and starting Microsoft in a new book, "Idea Man," that was excerpted in Vanity Fair Wednesday.

Here are some quick, juicy bits:

On Bill Gates' ambitions at age 13 when the two met at Lakeside high school:

"One day he showed me the (Fortune) magazine’s special annual issue and asked me, 'What do you think it’s like to run a Fortune 500 company?' I said I had no idea. And Bill said, 'Maybe we’ll have our own company someday.' He was 13 years old and already a budding entrepreneur."

On how Gates always wanted to be the smartest guy in the room:

"You could tell three things about Bill Gates pretty quickly. He was really smart. He was really competitive; he wanted to show you how smart he was. And he was really, really persistent."

Allen said Gates whittled down Allen's share in Microsoft from the beginning when the two started the company:

"From the time we’d started together in Massachusetts, I’d assumed that our partnership would be a 50-50 proposition. But Bill had another idea. 'It’s not right for you to get half,' he said. 'You had your salary at MITS while I did almost everything on BASIC without one back in Boston. I should get more. I think it should be 60-40.' ...

Bill’s intensity was nonstop, and when he asked me for a walk-and-talk one day, I knew something was up. We’d gone a block when he cut to the chase: 'I’ve done most of the work on BASIC, and I gave up a lot to leave Harvard,' he said. 'I deserve more than 60 percent.'

'How much more?'

'I was thinking 64-36.' ”

On how Allen was mad that Microsoft Chief Executive Steve Ballmer received 8.75 percent of the company when he joined Microsoft:

"Bill had offered Steve 8.75 percent of the company, considerably more than what I’d agreed to.

It was bad enough that Bill had chosen to override me on a partnership issue we’d specifically discussed. It was worse that he’d waited till I was away to send the letter. I wrote him to set out what I had learned, and concluded, 'As a result of discovering these facts I am no longer interested in employing Mr. Ballmer, and I consider the above points a major breach of faith on your part.' "

On how after Allen was diagnosed with cancer, he felt Gates and Ballmer felt he wasn't productive enough:

"One evening in late December 1982, I heard Bill and Steve speaking heatedly in Bill’s office and paused outside to listen in. It was easy to get the gist of the conversation. They were bemoaning my recent lack of production and discussing how they might dilute my Microsoft equity by issuing options to themselves and other shareholders. It was clear that they’d been thinking about this for some time."

Update 11:32 a.m.:

Bill Gates released this statement in response to Allen's book:

“While my recollection of many of these events may differ from Paul’s, I value his friendship and the important contributions he made to the world of technology and at Microsoft.”

Microsoft is not commenting on the book.

Update 3:14 p.m.:

Tell us whether you feel Paul Allen deserved a greater share of Microsoft in the poll below.