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Thread: Capacitor on monitor power supply

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    Capacitor on monitor power supply

    QUESTION FOR THE TECHIES
    Have a 19" monitor that's taken to going gray then black. It's an Optiquest Q9B-2, and looking around the net it seems they're know to go down due to bad capacitors. Every place I've read about it the most likely culprits are a pair of 1000uF 16V capacitors. I popped it open and neither of the two LOOK bad, but as the monitor is a paperwight right now I'm going to change them and see.


    PROBLEM: The two present are both 880uF 16V. Every reference I've seen says they're 1000uF 16V. I'm NOT an electronics guru (well, not to brag but I DID change the batteries in my flashlight)... but soldering components I've done, and a fix for a few bucks beats buying a new monitor.


    I'm just wondering if I should replace them with 1000uF 16V everyone SAYS is there or with exactly whats there, 880uF. Possibly this was a refurbished unit and someone used what they had?
    -- Do not meddle in the affairs of dragons, for you are crunchy and good with ketchup. --

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    Rob, 1000uF 16V is a very standard value for an Electrolytic capacitor and I never heard of a 880uF value before.

    Electrolytic capacitors dry out due to the heat in a monitor so sometimes need replacing. Aim for a low impedance type if you can such as designed for use in a power supply or monitor. Also, go for 105'C temperature rating. The absolute capacitance value is not very important in this case.

    Thinking about it more: the cap is probably a special switched-mode (low impedance) 680uF 16V. But try 1000uF

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    Thanks. I may have misread the 880, it was angled against the other. Either way, as you suggest (and others elsewhere concur)... will try 1000uF. This monitor is known for using cheap ones... can't recall the brand, but it's a known issue. Will try to get something that has a little better staying power.
    -- Do not meddle in the affairs of dragons, for you are crunchy and good with ketchup. --

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    Never, in 20 years give or take, have I had a monitor go bad.
    Hard drives, fans, anything else in the CPU case have gone bad.
    Even had a wife go bad (that's another story).

    But is it worth all this just to probably find out the monitor may or may not work again?
    Come on, wally world, best buy, frys.......
    All have monitors for sale cheap.

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    Quote Originally Posted by iowadawg View Post
    Come on, wally world, best buy, frys.......
    All have monitors for sale cheap.
    Not all of us live on a cushy government pension.

    The difference is about $200 to $300 versus $3 worth of parts and few minutes of time. I always try to fix stuff myself whenever I can, rather than buying new. If it normally works well, it can be worth fixing. Wives are a much more complicated topic . . .

    Capacitors have become a major failure point for a lot of products ever since most of the production moved to China. USA and Japanese-made capacitors are much higher quality. I've seen a few products advertised as made with "no Chinese capacitors."
    "Democracy is two wolves and a lamb voting on what to have for lunch. Liberty is a well-armed lamb contesting the vote." -- Benjamin Franklin


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    Cushy...yeah right!

    As the president said, and I am paraphrasing him here:
    You will have to give up your iphone, or cable tv, to get the monitor you need.

    And if you know where and when and what the president said?
    You do keep up with the news by not watching msnbc, cnn, etal.

    Thing is, more and more chinese made crap is in our products.
    Because too many companies are greedy as hell and buy the cheapest there is.

    Good luck on fixing your monitor.
    Do let us know.
    Unless it blows up and puts you in the hospital.

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    Everything I read about this monitor points to the same problem as the culprit.

    Radio Shack nearby didnt have the parts I wanted, so i went a slightly more expensive route and bought the pre-packed repair kit sold widely for this monitor, which includes the set of all but one large capacitor and a few trinkets like solder and a wick. I already had some credit at Amazon from a Christmas gift, so I'm actually not out of pocket, and some guy will make maybe 10 bucks on the deal for packaging the stuff and shipping it to my front gate. [I'd have spent $10 in gas going to buy another monitor.] The caps that come in the kit are of more reputable brands than the manufacturer used. The monitor is darned nice otherwise.

    I got a free computer once when my ex decided to replace the laptop I'd bought for my daughter as she entered college. It'd been ruled dead by her tech buddies at UT. I cleaned all the nasty RAM-sucking bullshit filesharing programs, removed a million pictures and video files that were about to max out the hard drive... and used it as my daily work computer for several years. Also stretched another PC three extra years by wiping the disk, putting on a real OP system (it had Win ME) and stuffing all the RAM it'd hold. It went from sounding like the flight deck of an aircraft carrier to purring like a kitten.

    My dad never to my knowledge replaced anything he could fix. In this case all signs point to me being able to salvage a monitor I paid several hundred for by replacing a few cheap components. Gotta give it a shot.
    -- Do not meddle in the affairs of dragons, for you are crunchy and good with ketchup. --

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    Quote Originally Posted by robjones View Post
    My dad never to my knowledge replaced anything he could fix. In this case all signs point to me being able to salvage a monitor I paid several hundred for by replacing a few cheap components. Gotta give it a shot.
    I can tell that neither your dad nor you experienced the luxury of a government pension.
    "Democracy is two wolves and a lamb voting on what to have for lunch. Liberty is a well-armed lamb contesting the vote." -- Benjamin Franklin


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    Dad was a depression era farmboy. Self-reliance wasn't a habit, more of a religion. Wasn't much the guy didn't know how to do.
    -- Do not meddle in the affairs of dragons, for you are crunchy and good with ketchup. --

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    Quote Originally Posted by robjones View Post
    Dad was a depression era farmboy. Self-reliance wasn't a habit, more of a religion. Wasn't much the guy didn't know how to do.
    That kind of life philosophy would not sit well with the White House these days. Obama could never draw your dad into the dark side.
    "Democracy is two wolves and a lamb voting on what to have for lunch. Liberty is a well-armed lamb contesting the vote." -- Benjamin Franklin


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