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The Mystery of the Burnt Thighs

[The film noir music rises as the scene fades in again on a 1950’s-style office, the glow of twin LCDs illuminating the back of a man staring out the window. His voice is low and harsh.]

People don’t come to me for comfort, they come to have their problems fixed. Quietly, if possible. Loudly, if not. Usually I can oblige, but sometimes a case is too big even for me. That’s what happened last week when I returned to my office after a stakeout to find not one, but two guys sitting in my waiting room.

It was hot, the air conditioning has been on the fritz since 1987, and both were wearing shorts and, judging from the bags at their feet, both were packing heat. One had a bandage on his leg. They looked uncomfortable and clearly didn’t know each other.

I pointed at the guy closer to the door, and motioned him to come into my office. Once we were seated on opposite sides of my battered desk, he launched into his tale of woe. He was Arlo Rose, a programmer, working on Konfabulator. I’d heard of his work – Konfabulator displayed tiny programs called widgets on the Mac, and he’d been the first on the block to do it. A nice living – all legal like – but then Apple took over his turf and told him to take a powder. He did, and ran right to another of the big bosses in town – Yahoo.

<http://widgets.yahoo.com/>

But he was here on personal business. He had fallen asleep coding Konfabulator, and woken up to burned thighs. He leaned over to pull something out of his bag to show me, but I wasn’t taking any chances. When he came up with his heat, he was staring into mine – a Colt pistol I keep in the top drawer for such situations. His heat wasn’t a firearm, but a MacBook Pro, so I lowered my piece. He hadn’t been expecting the pistol, and it rattled him.

It turned out his MacBook Pro was running hot. Really hot. Hot enough to burn both his thighs and an expensive coffee table. He wanted to know why, and if he was being set up by Apple because of some harsh words that had gone down during the Konfabulator deal. It was a good question, and one I didn’t know the answer to, so I told him to leave the MacBook Pro and come back the next day.

After seeing him out, I showed the second guy in. I figured it would be the usual – help ironing out a misunderstanding with a bookie, whatever. He introduced himself as Christian Heurich: a photographer, and a good one, to judge from the images I found while doing a background check.

<http://www.heurich.com/>

But unlike most photographers who come into my office, his problem had nothing to do with dames. He too had fallen asleep while working on his MacBook Pro – when he leaned over to get it to show me, I merely kept my finger on the trigger inside my desk drawer. And whereas Arlo had suffered only a mild burn, Christian had some nerve damage in his left leg as a result of tackling liposarcoma 18 years ago, so he hadn’t noticed the heat until he’d suffered a second degree burn.

Now I was intrigued. It’s not often I get two cases in one day, much less two identical problems. I told Christian to come back in a day too, and then sat down to think.

Laptops have gotten hotter over the years, as the manufacturers pack more and more power into their CPUs. A call to a doctor friend turned up the painful tale of a 50-year-old scientist who had managed to burn his privates with only an hour usage, fully dressed (or so he claimed). I winced at the thought and took a swig from the bottle in my desk. Forewarned is forearmed.

<http://ergo.human.cornell.edu/hotlaptops.html>

Arlo had said something about CPU usage being out of control, so I started to poke around. Indeed, his MacBook Pro was using 50 to 60 percent of its dual CPUs while idling. Why? I racked my brain, staring out my window at the darkening night, and as the streetlight across the street winked on, it came to me. Spotlight. A good technology in theory, though it’s never found anything for me that I couldn’t find myself faster. Perhaps I just know where to look. But Spotlight works by sneaking around in the background, reading everything it can find, and that can chew CPU for no apparent reason.

Unfortunately, checking Activity Monitor for Spotlight’s prints – the mds and mdimport processes – revealed little. It might have been there, but it wasn’t the cause right now. I turned back to the window and stared down at the drunks on the sidewalk. My office isn’t in the best part of town. OK, it’s not even in a decent part of town. But sometimes you have to be near the lowlifes to find out what’s going on.

I stepped out for a bit of air that wasn’t necessarily fresh, particularly as I passed a guy who’d been a whiz kid before he got strung out on World of Warcraft. Now he bummed money until he had enough to get a few hours in a dive Internet cafe. Swore he’d find some treasure and then be able to sell it on the eBay black market to set himself up again. I passed him a few bucks and asked what the word on the street was. He looked up at me, looked back down, and in a low voice fingered Windows File Sharing.

I should have known. Windows File Sharing is how Apple made Macs play nice with Windows-based networks, and you have to know how those Apple guys must have hated being forced to write code to work with Windows. Perhaps it was spite, but more likely they were just doing the minimum. Back at the office, I turned off Windows File Sharing on Arlo’s MacBook Pro, the CPU usage dropped, and after a bit, it was noticeably cooler, though still hotter than the Roxy on a Saturday night.

That night I went trolling for info. Sources confirmed that lots of MacBook Pro owners were having similar problems, though few had the burns that Arlo and Christian experienced. When pressed for details, a number of people said they’d returned their MacBook Pros to Apple for repair. Sometimes they came back with little change, other times they ran a bit cooler, though still uncomfortably warm. Thermal grease was blamed in some cases, motherboards were replaced, serial numbers were reset. An SMC firmware update helped some users.

<http://discussions.apple.com/thread.jspa? threadID=491878>

<http://www.apple.com/support/downloads/ macbookprosmcfirmwareupdate.html>

I began to smell a rat. The natives were restless, and Apple was backpedaling on using the MacBook Pro or other notebook computer on your lap. Indeed, the only instance of "laptop" in the Apple Knowledgebase referred to Windows laptops. Was Apple pretending that laptops couldn’t be used safely on laps? Some problems were just stupid, like the MacBook (not Pro) overheating because a piece of plastic had been left in at the factory.

<http://www.informationweek.com/news/ showArticle.jhtml?articleID=187900365>

<http://docs.info.apple.com/article.html? artnum=30612>

<http://docs.info.apple.com/article.html? artnum=303848>

Despite the talk, people were making do. I learned about a couple of utilities called CoreDuoTemp and Temperature Monitor that would report on the internal temperatures of the MacBook Pro. Others recommended the CoolPad from Road Tools to get the MacBook Pro off the lap.

<http://macbricol.free.fr/coreduotemp/>

<http://www.bresink.com/osx/ TemperatureMonitor.html>

<http://www.roadtools.com/>

The next day, I returned Arlo’s MacBook Pro, now running a bit cooler, and recommended that both he and Christian keep their MacBook Pros off their laps. I told them everything I’d learned, but I didn’t have the answers they wanted. Apple clearly knew about the problem, and was working on fixing it, but true to form was keeping quiet. They couldn’t pay me enough to try to pry information out of Apple. People have disappeared doing that.

In the end, I gave them the name of a reporter I knew at the local paper. Maybe it would make a story, and maybe Apple would take notice. But more likely Apple would never admit to the problem and it would eventually disappear, buried in the desert along with the news of exploding batteries, Power Macs that sounded like wind tunnels, and other missteps. It’s an ugly business sometimes, and sometimes good people get hurt. Arlo and Christian got hurt, but they’ll heal.

And me, I’ve seen it all, so nothing hurts me any more.


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