Repair of the Week

A MacBook came in over the weekend showing graphic anomalies on the screen almost immediately after pressing the power button. Horizontal lines are easy to diagnose: graphics processor failure. Vertical lines are easy, too: failure of the panel itself. But the patterns on the screen could be any number of things, from the panel itself, to the low voltage display cable, to the graphics processor, to software. I ordered up a main logic board.

By assuming failure of some part of the graphics processing system, I went ahead and ordered a main logic board. After installing it, and noticing the same exact problem, I reconsidered my diagnosis. What are the odds that the same exact pattern would appear from two graphics processors suffering the exact same failure?

After scratching my head for a while, I stepped back and went to Apple’s MacBook service manual. There are great step by step troubleshooting guides for every conceivable issue, and while I like to think I have them all memorized, in this case I messed up.

Remembering that the main system RAM is shared with the graphics processor, I pulled one of the chips from the user-accessible slot. Problem solved. Since the RAM was from us and covered by our lifetime warranty, parts and labor were covered. I only wish I thought of this before keeping the customer’s machine longer than I had to!

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  • FEATURED SPECIAL | 01/20/09 – 01/27/09

    Remember the quality keyboards of yesteryear that had clickity keys and real mechanical keyswitches? For the past few years, Matias has been offering the Tactile Pro, which uses old-school keyswitches along with modern touches, such as USB 2.0 ports. They have the feel of Apple and IBM keyboards of 15 or 20 years ago.

    Based on the legendary Alps keyswitch used in the Apple Extended Keyboard and the original Tactile Pro, the Matias Mechanical Keyswitch recreates the tactile feedback and force curve of the original Alps design, ensuring maximum performance, greater comfort, and faster typing speeds. You will feel the difference immediately.

    We recently learned that Matias has discontinued the white Mac-only version of the Tactile Pro 2.0. This model has ™ and other typographic symbols printed right on the keys. Simply hold down the Option key for the bottom-right characters, or Shift and Option for the top-right characters. This means you won’t need to launch other applications to find hard to remember key combinations for international characters, accents, punctuation, mathematical and currency symbols.

    We only have a few of the white Tactile Pro keyboards in stock. They are on sale for $124.99. Once these sell out, we’ll only have the black and silver model in stock. This also has the real keyswitches, but does not have the Mac typographical symbols printed on it.

    See this “by clicking here.”:http://www.smalldog.com/product/43082

  • Follow Us On Facebook and Twitter!

    Remember to sign up to become a fan of Small Dog on Facebook! We will continue to randomly choose two contest winners per month from our Facebook fans as January comes to a close. We are about to choose a Twitter friend by this Friday.

    If you’re not already in our Facebook group, you can join here:
    “Small Dog Electronics on Facebook.”:http://www.facebook.com/pages/Small-Dog-Electronics/18904017006

    Not on Facebook? “Sign up here.”:http://www.facebook.com

    Do you use Twitter? We post Mac tips, tricks, news, contests and more on our Twitter feed. “Small Dog Electronics on Twitter.”:https://twitter.com/hellosmalldog

  • Small Dog Expansion Plans

    Times are tight right now, but Small Dog Electronics vows to make this a productive and successful year. We are hoping to expand this year, and Don was recently interviewed by the Burlington Free Press about our plans for the future.

    “Read the whole article here!”:http://burlingtonfreepress.com/article/20090119/BUSINESS/90118012&referrer=FRONTPAGECAROUSEL

  • Happy Tuesday,

    Once or twice each generation, there are perhaps a handful of days that most people on this planet will remember for the rest of their lives. It’s tough to argue that today isn’t one of them, regardless of your political affiliation or preferences. I am overjoyed not only to see the racial barrier fall and the fulfillment of Dr. Martin Luther King’s dream, but also to finally have a change in leadership after President Bush’s two terms in office.

    Our network at the Small Dog headquarters in Waitsfield was overwhelmed with employees trying to stream video of the inauguration. We operate on a 1.5 megabit T1 connection for our private network, and a six megabit DSL network for our showroom, so it’s not too surprising we had some issues. In the end, many of us tuned to Vermont Public Radio or gathered at the plasma screen in the showroom to watch history unfold from The New York Times’ video stream.

    Here’s to the change we so desperately need.

    Keep in touch,

    Matt
    matt@smalldog.com

  • Zombie Computers 101

    I was recently forwarded an email from a customer who is having issues with his portable computer waking from sleep, and sometimes even going to sleep. He, like many people with similar issues, wants to know why. Unfortunately, there is no one-size-fits-all solution, and sight-unseen, there’s no real way to diagnose the machine. Since it’s such a common occurrence, though, let’s talk about possible scenarios.

    For a machine not waking properly from sleep, there are a few basic troubleshooting steps that one can take before bringing the computer in for service. They can try resetting their PRAM, which clears out the Non-Volatile RAM that may have corrupt settings stored in it. Resetting the System Management Controller or Power Management Unit (depending on the machine) is the next step as that clears out potentially corrupt preferences in how your system is controlling power.

    If neither of those works, or if it only works temporarily, the next step is usually to try an Archive and Install of the system software, or if you have a good backup and want to really be thorough in your troubleshooting, you can try an Erase and Install. There are a few folks out there who believe an Archive and Install is the placebo equivalent of a school nurse taking your temperature for a broken leg, I firmly believe that is not the case and have seen many a bizarre software glitch fixed with a simple Archive and Install. Fresh operating system = Good Times.

    So let’s say you’ve done all of that, and still your machine doesn’t wake properly from sleep. My next troubleshooting step would be to try known-good RAM. RAM can be a sneaky culprit as the processors are constantly transferring information to and from it for quick access. If the RAM is failing, this can cause software corruption. This is particularly frustrating when one has a system that is constantly becoming corrupt but always resolves temporarily after an Archive and Install. While there are plenty of at-home memory tests out there, they can often produce false-negatives (and even in rare cases false-positives). Want to rule out memory? Try running the machine with a fresh chip, run another Archive and Install and see if the issue reoccurs.

    Have you now done everything above and are still having issues? It might be time to bring it in for repair. While at this point some technicians make the mistake of jumping right to the logic board, often times sleep issues are caused by a defective sleep sensor. This is more likely in the case of a machine that puts itself to sleep (as opposed to one that has trouble waking up). In rare cases, a defective temperature sensor or flex cable can cause sleep/wake errors as well.

    There are two more machine-specific hot tips to check that could help your technician diagnose the issue. First off, if you have a 15″ PowerBook that is putting itself to sleep, check the Console logs and if you see “PMU Overtemp” you most likely need your top case replaced (where the sleep switch on that model is located). Have a MacBook Pro that’s waking up in your bag or when you pick it up closed from the right-hand side? That most likely needs a top case too.