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A Bit of History Behind the Mac OS X on Intel Project "Marklar"

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intelApple's announcement to move their Macs from PowerPC to Intel processors in 2005 was a huge surprise at the time. Serious reports about the plan hit the web only two days before the official announcement at WWDC 2005. The immediate reaction on MacRumors included a 2936 comment thread with some very strong reactions to the switch-up.

Now, a post by the wife of a former Apple employee at Q&A site Quora fills in some fascinating details about the Mac OS X on Intel project.

According to Kim Scheinberg, she and her husband John Kullmann had decided to move back to the east coast in 2000. In order to make the move, Kullmann had to work on a more independent project at Apple. Ultimately, he started work on an Intel version of Mac OS X. Eighteen months later, in December 2001, his boss asks him to show him what he's been working on:

At this point, JK has three PCs in his office at Apple, and another three in the office at home, all sold to him by a friend who sells custom built PCs (can't order them through the usual Apple channels because no one in the company knows what he's working on). All are running the Mac OS.

In JK's office, Joe watches in amazement as JK boots up an Intel PC and up on the screen comes the familiar 'Welcome to Macintosh'.

Joe pauses, silent for a moment, then says, "I'll be right back."

He comes back a few minutes later with Bertrand Serlet.

Max (our 1-year-old) and I were in the office when this happened because I was picking JK up from work. Bertrand walks in, watches the PC boot up, and says to JK, "How long would it take you to get this running on a (Sony) Vaio?" JK replies, "Not long" and Bertrand says, "Two weeks? Three?"

JK said more like two *hours*. Three hours, tops.

Bertrand tells JK to go to Fry's (the famous West Coast computer chain) and buy the top of the line, most expensive Vaio they have. So off JK, Max and I go to Frys. We return to Apple less than an hour later. By 7:30 that evening, the Vaio is running the Mac OS. [My husband disputes my memory of this and says that Matt Watson bought the Vaio. Maybe Matt will chime in.]

The next morning, Steve Jobs is on a plane to Japan to meet with the President of Sony.

More engineers were assigned in 2002, and she says that's about when rumors of the project started to appear.

Indeed, in August 2002, we reported on the first news report about Marklar from eWeek:

According to sources, the Cupertino, Calif., Mac maker has been working steadily on maintaining current, PC-compatible builds of its Unix-based OS.

At the time, it was described as a "fall-back plan", in case the PowerPC should fail to deliver. Later, reports would also claim that PC manufacturers were wooing Steve Jobs to allow them to license Mac OS X and sell PCs running Apple's operating system.

Ultimately, Apple decided to transition from the PowerPC to Intel processor in 2005. The transition was a success, and all Macs now run on Intel processors.

Top Rated Comments

188 months ago
I always enjoy learning about this aspect of the long transition from OS 9 and PPC to OS X and Intel, but I think it is disingenuous to present these stories as if the achievability of the task was uncertain and its completion was a surprising, watershed moment that got vice presidents to stop what they were doing and put Steve on an airplane.

OS X was promised for Intel; Apple shipped developer previews of OS X (as Rhapsody) for Intel. I have a copy of Rhapsody DR2 and have installed it on commodity PC hardware. It was a surprise and a let-down for developers when Apple decided to reneg on shipping the Intel version along with Yellow Box (Cocoa) for Windows. Rhapsody DR2 was released in 1998, this effort began in 2000 (before OS X 10.0, actually), so at most there is a two year gap where the status of the port is uncertain. It is likely that it was kept maintained for at least part of the gap, especially since Darwin was publicly released as an open-source project with Intel support in April 2000. What do you suppose the Intel version of Darwin was there for? No reason? It is certainly possible that in the crunch to get OS X to 10.0 for PPC the Intel port fell by the wayside and perhaps was no longer feature-complete, and this guy's job was to get it caught up, but it was still something they had sitting around the whole time.

That the Intel port could go from something they were already shipping in developer previews to something nobody within Apple even knew existed simply doesn't make sense. I understand that there were commercial reasons for Apple to maintain public silence on the topic, and to be very clear that their employees were expected to do the same, but I'm not about to believe these people convinced themselves that something they already knew existed as a shipping product didn't actually exist after all! In the wider world, the fact that Apple had maintained an Intel port of OS X was one of the worst-kept secrets in computer industry history. I agree that the actual time and place of the Intel switch announcement was a complete surprise, but the fact that the possibility existed was established when NEXTSTEP was released for Intel in I believe 1993.
Score: 12 Votes (Like | Disagree)
Nermal Avatar
188 months ago
The next morning, Steve Jobs is on a plane to Japan to meet with the President of Sony.

I wonder whether this means that Steve was considering licensing out OS X.
Score: 11 Votes (Like | Disagree)
Mike Oxard Avatar
188 months ago

I would be absolutely THRILLED if the macrumors admins made it a rule that any behaviour that displays such devotion lacking logic and rational be BANNED completely. All such posts should be removed as to contribute to an OBJECTIVE conversation in the forums without any fanboyism. I'm sick of it.

I get the feeling you are in the wrong place.
Score: 9 Votes (Like | Disagree)
antonis Avatar
188 months ago
IBM can blame themselves for losing a big partner like Apple on this. They failed to deliver a G5 (or any processor faster than Motorolla's G4) for the laptop series. Apple laptops were stuck with aged and underpowered G4 for a long time waiting for IBM to deliver something new. Apple had to move on eventually, or lose the laptop market entirely.

I'm not glad to say this, though. PowerPC processors seemed to have a better architecture, leading to a great performance on lower clock speeds than Intel's cpus.
Score: 9 Votes (Like | Disagree)
bushido Avatar
188 months ago
this old stuff is always fun to read and comments seem to have been far more professional and technical back then too

Dear me of the future:

lol (laugh out loud, incase thats no longer used in 10 years) i know i know we were pretty silly arguing about iPhone 5 (?) rumors and Samsung (it was the company that always "stole" from apple you remember?) fights.

is the iPhone still around? i guess not. looking forward to get a reply by myself in 10 years. till then. DONT DIE!
Score: 7 Votes (Like | Disagree)
arn Avatar
188 months ago
I wonder whether this means that Steve was considering licensing out OS X.

that's what I was thinking.

arn
Score: 7 Votes (Like | Disagree)

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