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heat guns, Macintoshes, and freedom manifestos
Thursday, March 8 2007
Since the recent drive down to Silver Spring and back, my 700 MHz iBook G3 (which I use as a travel computer; it's been to the Galapagos, Guatemala, Ecuador, and Charlotteville) started manifesting a peculiar unreliability in its screen brightness. It would seem to fluctuate wildly from full brightness all the way down to absolute darkness. From shining a light through the Apple logo in the back of the screen, I could see that the content of the display was unaffected even when it was completely dark. The problem was the backlight. Normally with such symptoms it would be natural to conclude that the problem was either the connection to the backlight's bulb or else the cable supplying signals to it. As with all laptops, these signals pass through a space inside the screen hinge and can (like the tendons whipsawing against wrist bones and nerves in carpal tunnel syndrome sufferers) experience wear. But if that were the case, the backlight should flicker most when the screen is being raised and lowered. With my iBook, though, the screen flickered most when I applied pressure just below the left side of the keyboard. After much research, I discovered that iBooks are infamous for this problem and there was once even an Apple policy of fixing it no matter the state of the iBook's warranty coverage.
(During my research I was repeatedly buffeted by an irritating tendency among Macintosh fanatics to waste valuable ink expatiating on the particulars of their warranty coverage. For some reason Mac people, who tend to be both better-educated and wealthier than average, make the statistically-bad decision to buy extended warranty coverage plans for their machines. This is another way of saying that they pay a tax for being mathematically ignorant. While I see the value of a warranty as an incentive preventing manufacturers from routinely delivering shoddy products and I admit it's good to have recourse when a non-functional device arrives in the mail, beyond that, a warranty is nothing more than another restriction on freedom of the sort to which I personally refuse to abide. This is because it's my view that anything I buy is both fully mine yet not fully satisfactory to my needs. And making do with an unmodified product is just another way of selling out to the Man, however trivially. There's a manifesto in here somewhere, and it's clear that it's alien to the manifestos of Macintosh culture, to which I can never belong.)
Back to the screen problem. It turns out that the symptoms of my iBook represented solder failures beneath the main video processor (manufactured by ATI) on the motherboard. This processor is a large ceramic square that makes contact to the motherboard through a connection technology called ball grid array. In this technology, all the connections between the chip and the board are hidden by the chip itself. The chips sits upon a grid of tiny solders that form when the whole thing is baked in an oven. Over time, though, the board beneath the chip can flex and the solders can crack, leading to bad, unpredictable connections. Evidently my glitches are nothing compared to those experienced by others; many people with this problem suffer crashes every time their computer is flexed, bumped or jostled. Surprisingly, though, there is a DIY fix. It involves using a heat gun or a propane torch to slowly and gently heat the massive ATI chip until the solders beneath it remelt and reform, good as new. I'm surprised a silicon-based chip can survive generalized and prolonged heating to the melting point of solder, but the number of success stories with this technique suggests that it's not even all that risky, so long as one protects parts of the computer not being heated (and refrains from bumping anything while the solder connections are fluid).
There has even been one person who, lacking a torch or heat gun, resorted to heating the ATI chip with a tea light, although he was needlessly foolish with the procedure, actually starting up his iBook while the chip was still heated to the melting point of solder! From everything I know about semiconductor junctions and the risk of runaway thermal effects, that was a very bad idea.
I'm guessing the heat gun technique can be used to revive all sorts of dead digital equipment having faulty ball grid array connections. With that in mind, today I placed an order for a heat gun from a retailer located on one of the many interwebs.
For linking purposes this article's URL is:
http://asecular.com/blog.php?070308 feedback
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