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LCD Monitors- how to choose ?

Discussion in 'Electronic Repair' started by pg, Jan 31, 2008.

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  1. pg

    pg Guest

    LCD is replacing CRT. This happens in my company also.

    My company has been buying LCD monitors to replace the CRT monitors,
    in stages. When old CRT dies, we replace it with an LCD. No problem
    there.

    Problem arises one or two years afterwards. The LCD monitors started
    to die off. Actually, it's not the LCD that conked. It's the
    fluorescence tube behind the LCD that quit working.

    When we were using CRTs, it normally lasted 5 to 7 years before it
    gives us problem. Now with LCD monitors, the attrition rate is just
    too high ! I mean, after a year or two and many started to drop like
    flies. It's getting to the point that it ain't funny anymore.

    With CRT monitor, if there is any problem, most of the time we can get
    someone to repair it. With LCD monitor, once the fluorescence tube
    refuses to shine anymore, there is no way to replace it. The damn
    thing is fused/glued together at the back of the LCD panel in such a
    way that it is next to impossible to remove/replace the tube. Even if
    we can remove the fluorescence tube, we can't find anyone who sells a
    new tube !

    So it's a total write-off. No remedy. No nothing. Nada.

    Of course we are replacing the dead LCD monitors with new LCD
    monitors, but I need help.

    I've read somewhere that some new LCD monitors got their back-lighting
    from LED arrays, rather than the useless fluorescence tube, and the
    one uses LED arrays can last longer.

    The thing is, when we go to buy LCD monitors, often there is no
    indication which brand / model uses the fluorescence tube, and which
    brand / model uses LED arrays.

    I've also heard that many manufacturers outsource their LCD monitor
    production to companies in China or India, and there are LCD monitors
    with the exact brand and model, a batch may comes with LED array
    backlighting, but another batch, perhaps from another plant, comes
    with fluorescence tube.

    Therefore, my question to all of you is this:

    How do I know **FOR SURE** which brand and/or which model of LCD
    monitors are equipped with LED array backlighting ?

    Thank you !
     
  2. James Sweet

    James Sweet Guest


    The fluorescent tubes can be replaced, I've done it on a number of LCD
    monitors. It's no walk in the park, but it's far from impossible.

    Yes some now have LED backlights, though high brightness LEDs don't last
    forever either and it remains to be seen how well they hold up in this
    application. LED backlight technology is relatively new, if a monitor uses
    it, it will probably say so prominently.

    Another option is to buy CRT monitors, they're a dime a dozen, I wouldn't
    trade mine for anything.
     
  3. Guest

    Wow, your a real downer. I just got an LCD monitor that I had hoped
    would last 5 yrs or more.

    I don't know if this will help but you can search the FCC numbers, you
    can get who built it and more info than the specs.

    https://www.part68.org/tteSearch.aspx
    or
    https://fjallfoss.fcc.gov/oetcf/eas/reports/GenericSearch.cfm

    A very good FCC search was www.part68.org/tte.cfm but it's 404 now
    --

    When a CNN split screen shows a white person, then a black person,
    then a white person, the anchor has the presence of mind to call it a
    "Reverse Oreo." It's not news, it's CNN. - Fark.com
    http://tinyurl.com/38x92l
     
  4. JANA

    JANA Guest

    If you go with the big name brand names in monitors, you will get LCD
    monitors that will last a long time. We are buying the Viewsonic and NEC
    professional series. Most of them are lasting about 4 to 5 years. After they
    wear out, we replace them. We started buying them about 7 years ago when
    they were very expensive. The payoff was very good from these.

    With the LCD monitors our clients found that employees complained much less
    about the strain of working for long periods in front of the computers. The
    amount of sick days went down. There was also some savings on power usage.
    There is a huge savings on useable desk space.

    The LED backed LCD monitors are much more expensive. It will be indicated on
    the monitor or in its spec sheet if it is LED backed. Apparently, the LED
    ones have their problems, because these LED's are working at very high
    intensity.

    As for replacing the backplane lamps on LCD monitors, on some models this is
    possible. But, it is time and work intensive. You will also have to research
    what type to buy and where to buy them from for the model type that you
    have. The monitor manufactures will only sell service parts to their
    authorized service reps.

    --

    JANA
    _____


    LCD is replacing CRT. This happens in my company also.

    My company has been buying LCD monitors to replace the CRT monitors,
    in stages. When old CRT dies, we replace it with an LCD. No problem
    there.

    Problem arises one or two years afterwards. The LCD monitors started
    to die off. Actually, it's not the LCD that conked. It's the
    fluorescence tube behind the LCD that quit working.

    When we were using CRTs, it normally lasted 5 to 7 years before it
    gives us problem. Now with LCD monitors, the attrition rate is just
    too high ! I mean, after a year or two and many started to drop like
    flies. It's getting to the point that it ain't funny anymore.

    With CRT monitor, if there is any problem, most of the time we can get
    someone to repair it. With LCD monitor, once the fluorescence tube
    refuses to shine anymore, there is no way to replace it. The damn
    thing is fused/glued together at the back of the LCD panel in such a
    way that it is next to impossible to remove/replace the tube. Even if
    we can remove the fluorescence tube, we can't find anyone who sells a
    new tube !

    So it's a total write-off. No remedy. No nothing. Nada.

    Of course we are replacing the dead LCD monitors with new LCD
    monitors, but I need help.

    I've read somewhere that some new LCD monitors got their back-lighting
    from LED arrays, rather than the useless fluorescence tube, and the
    one uses LED arrays can last longer.

    The thing is, when we go to buy LCD monitors, often there is no
    indication which brand / model uses the fluorescence tube, and which
    brand / model uses LED arrays.

    I've also heard that many manufacturers outsource their LCD monitor
    production to companies in China or India, and there are LCD monitors
    with the exact brand and model, a batch may comes with LED array
    backlighting, but another batch, perhaps from another plant, comes
    with fluorescence tube.

    Therefore, my question to all of you is this:

    How do I know **FOR SURE** which brand and/or which model of LCD
    monitors are equipped with LED array backlighting ?

    Thank you !
     
  5. pg

    pg Guest

    With 10 to 20 dead LCD monitors a week, of different brand / model,
    there is just no way we can pry open all of them, get the darn
    fluorescent tube out, look up a supplier online (seems that only the
    online suppliers sell the tubes), go buy from the supplier, and try
    putting the damn skinny tube back into that little space.

    No way. It's just no f*cking way !

    And the darnest thing is that the LCD monitors all use DIFFERENT &
    INCOMPATIBLE TYPES of the fluorescent tube ! Why can't they just unify
    the design into one-single-type-of-fluorescent-tube so that people at
    least can buy the thing anywhere, and replace them when necessary?

    Can you imagine if the fluorescent lamp to light our house are of many
    different and incompatible size / style / power-grading? Would you
    even use the fluorescent lamp in the first place ??

    Why can't they just standardize that damn fluorescent tube they put at
    the back of the LCD monitors?

    That's why our warehouse is piling up with dead LCDs, almost brand new
    (the most 2 year old).

    Nowadays people are talking about "GREEN STUFFS" and everyday I look
    at the pile of dead LCD, I dunno if I would laugh or cry.

    They say CRT is poisonous. They say CRT ain't "GREEN" because it has
    lots of lead. Yet, CRT last up to 9 years, and in most cases, they can
    be repaired with ease.

    In other words, CRT is actually MORE "green" than the LCD.
     
  6. Guest

    There is an off the wall way to be offered only LED LCD monitors.

    The mercury in fluorescence tube are a hazardous material, you can you
    can turn green and demand only LED LCD monitors. Or require a MSDS for
    each monitor

    MSDS for Mercury
    https://fscimage.fishersci.com/msds/96252.htm

    I know it's off the wall.
     
  7. James Sweet

    James Sweet Guest


    That's a LOT of monitors for sure.

    Sell them on ebay, LCDs with dead backlights do/did fetch a surprising
    amount.

    It's all about cost, for consumer use they will usually last until they're
    obsolete, are you using low end consumer grade monitors or good professional
    grade?

    We have some at work that are much older than 2 years which still work fine.
    Is power saving enabled to turn them off when not in use?

    Some people swear by these things, they do save a lot of space and energy,
    but we've got a few high end LCDs and even those don't look nearly as good
    to my eyes as a good and properly adjusted CRT. Sure you automatically get
    perfect geometry and convergence, but there's still an "LCD look" to it, I
    have no better words to describe it, but the image looks unnatural, and yes,
    I always run them at the native resolution for the panel.
     
  8. pg

    pg Guest

    Thanks for the info !
    Dunno. We got them from the suppliers. Mostly Taiwanese and Korean
    brands, such as Acer or BenQ or Samsung or LG.

    We get them by the specs - bow many inches 17", 19", 21" - wide-screen
    or regular, and the specs are determined by the department heads.
    We do have some that still working. It's the dead ones piling up here
    - they are two years old or less. What a waste ! !

    I mean, why should people throw the whole thing away when it's the
    fault of a tiny fluorescent tube ? Why they have to make it such a way
    that the tube is next-to-impossible to be replaced ?
    Dunno. There are just too many of them, and most of the users are just
    users - tell them about "power saving" and their eyeballs fall out.
    Personally I still use CRT. Perhaps I'm old fashion.

    Company replacing the CRT with LCD because it'd be counted as expenses
    - and that is good for the company in a sense - don't need to pay so
    much taxes.
     
  9. jakdedert

    jakdedert Guest

    pg wrote:
    I have a friend who works IT for a large law firm. He's had to replace
    an inordinate number of Dell lcds'. Recently it came across his desk
    that his firm has been engaged to handle a class-action against Dell for
    a particular model monitor which fails prematurely.

    He's a little conflicted over the situation, because he was the one who
    negotiated the Dell contract, and still has to deal with Dell support
    concerning the (probably) thousands of Dell products in use at the firm....

    jak
     
  10. Not that off the wall though! All electronic equipment now has to ship with
    a RoHS or WEE declaration, check it for the presence of mercury (Hg) and if
    it's present, it's got a fluorescent backlight, if not then it's another
    technology, almost certainly LED (although there are some TFT panels with
    electroluminescent backlights, not sure how big they get though).
    Martin
     
  11. Andy Cuffe

    Andy Cuffe Guest

    ....
    ....

    What brand of LCDs are you buying? This is awful reliability for an
    LCD! Even if you run them 24/7, they should be lasting about the same
    amount of time as a good CRT.

    I haven't seen many LCDs with bad fluorescent tubes. All the bad ones
    I've seen still worked, but were dim, or off color. If the back light
    is completely out, then the inverter is usually the problem, not the
    bulbs.

    By far the most common problem with cheap LCD monitors is the power
    supply (usually bad caps).

    If you stick to a big name brand such as NEC or Samsung, they should
    last a lot longer. Turn the brightness down to about 50% and use
    power saving if you want them to last longer. I'm typing this on a 9
    year old LCD which is still plenty bright.
    Andy Cuffe

     
  12. mike

    mike Guest

    EVERY wrist watch I've owned has failed. There's a little wheel inside
    that goes back and forth. It's always stopped going back and forth.
    Why don't they make it so I can take it apart with my gas pliers and 10"
    screwdriver. Why can't I go to Ace hardware and buy a new little wheel?
    Can't cost more than 10-cents. But they want $40 to fix my watch.
    Or better yet, why can't they just make a more reliable little wheel?
    I'm sick of throwing away perfectly good wrist watches.

    And don't get me started on all those parts in my automobile...

    Corporations do the best job they know how given their available
    technology to maximize THIER profit. Somtimes, that's consistent
    with maximizing YOUR return on your investment. But $#|^ happens...
    Doesn't matter how reliable it is if it costs a dollar more, because
    MOST of us won't buy it. The reason you don't GET better stuff is
    because not enough people are willing to PAY for better stuff.
     
  13. mc

    mc Guest

    They do. I have a lab full of LCD monitors some of which are 3 or 4 years
    old at least, and we haven't had any failures at all. I don't know why pg
    is having such a high failure rate.
     
  14. Plenty do. A reasonable life would be about 10,000 hours use.
     

  15. Not true. A lot of electronics is exempt. It's only the crap they
    dump on unsuspecting consumers that is to be lead free.


    --
    Service to my country? Been there, Done that, and I've got my DD214 to
    prove it.
    Member of DAV #85.

    Michael A. Terrell
    Central Florida
     
  16. Andrew Barss

    Andrew Barss Guest

    : If you go with the big name brand names in monitors, you will get LCD
    : monitors that will last a long time. We are buying the Viewsonic and NEC
    : professional series.


    Which series are these? I'm looking for a very good, very bright 22" or 24"
    LCD.

    -- Andy Barss
     
  17. Perhaps I should have added 'outside of the USA'; I know that this is the
    case, I work for a large industrial electronic equipment manufacturing
    business and we have been forced into producing RoHS compliant designs;
    technically WEE applies to consumer goods but you can hardly say 'This TFT
    display is for industrial use only' ;-)
    Martin
     
  18. Guest

    I'm hoping it's the Viewsonic VX2255, cause that's the one I have :)

    and JANA will never reply, S/he post and that's it.
     
  19. Guest

    Hi!
    What brand and model are the monitors you are buying?

    I ask because I suspect that there is something that all these
    monitors have in common (other than a fluorescent backlight tube) that
    is causing the failure.

    Also--how are these panels being used? Are they being left on around
    the clock? Is the environment they operate in a harsh one--is there
    high humidity or something else that would be hard on electronics?
    I really can't help but think that it is something about the monitors
    you have purchased, or something about how they are being used that is
    causing this kind of failure.

    I too have a large number of Samsung Syncmaster LCD panel monitors
    under my control, the majority of which are at least four years old.
    They are kept on during normal business hours, although a screen saver
    comes on after a while. Not a one of these has failed.

    Secondly, while it is not the easiest thing to do, replacement
    backlights are available and can be installed if you're willing to
    take the time.

    LED-based backlighting is still a rather new idea, and only a few
    panel makers are presently using it. I'm not aware of any desktop flat
    panel displays that are backlit with LEDs, but some may already be on
    the market. As to whether or not they'll be more reliable--in theory,
    the reliability should be every bit as good as a fluorescent backlight
    or even better. LEDs last a very long time.

    Another thing I can think of--if you haven't already, try turning the
    brightness down. An awful lot of monitors are sold with the brightness
    turned all the way up. This is unnecessary and could shorten the
    lifetime of the backlight.

    I'd also look at the power coming to the monitors--is the circuit to
    which they are attached working properly and large enough to stand the
    load? If it isn't...this could be another possibility.
    Any reputable company that is selling a display model claiming to
    feature LED backlighting should be assurance enough. As long as you're
    dealing with a reputable manufacturer or company, you will get what
    you expect to be buying.

    William
     
  20. Heh - Got news for you - 99% of ALL LCD monitors shipping today
    (worldwide)
    are RoHS compliant, have WEE declarations.... AND use CCFL backlights. Less
    than 1% currently use LED technology.

    The only way to check on backlight technology is looking for specifics by
    the
    monitor manufacturer. LED backlights are NOT common yet. If they are used,
    it is more typically for performance reasons, such as wider color gamut, and
    the extended life just happens to be an additional benefit.

    I speak from experience.
    NGA
     
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