Professional Web Applications Themes

CRT randomly loses power? - Linux Setup, Configuration & Administration

Hello everyone! Over the past several weeks, my monitor has started to blank out at random (and frequent) intervals. Some days, it happens once every hour or so, other days it happens every 30 seconds. The monitor's power LED stays green, but the CRT itself loses power. Note that it doesn't appear to be going into power-save mode, as the LED doesn't turn amber... the CRT tube simply loses power. Turning the monitor off and then on brings it back to life. My (desktop) system: - Redhat Linux 9.0, fully updated via Redhat Network - Stock kernel 2.4.20-20.9 with glibc ...

  1. #1

    Default CRT randomly loses power?

    Hello everyone!

    Over the past several weeks, my monitor has started to blank out
    at random (and frequent) intervals. Some days, it happens once
    every hour or so, other days it happens every 30 seconds. The
    monitor's power LED stays green, but the CRT itself loses power.
    Note that it doesn't appear to be going into power-save mode, as
    the LED doesn't turn amber... the CRT tube simply loses power.
    Turning the monitor off and then on brings it back to life.

    My (desktop) system:
    - Redhat Linux 9.0, fully updated via Redhat Network
    - Stock kernel 2.4.20-20.9 with glibc 2.3.2
    - Athlon 1800+ running on an ECS Mainboard K7S5A motherboard
    - NVIDIA GeForce 440 MX video card
    - NVIDIA accelerated Linux driver v1.0-4496
    - NEC MultiSync 97F CRT monitor (running at 1280 x 1024)

    Note that this is a dual boot system, and I experience none of these
    problems when running Windows 2000. Another possibly related
    issue is that the right side edge the screen is slightly compressed, as if
    the CRT tube was aimed wrong or a magnet was nearby. No amount
    of adjusting the monitor controls relieves the problem. Again, this
    issue doesn't show up in Windows, was not the case in Linux a month
    ago, and I can't think of any system changes I made that would cause
    this. I'd also add that I had a borrowed LCD monitor a few months
    ago and had no problems with it either under either OS.

    I'm running out of ideas.... can anyone offer some suggestions?

    Many thanks!

    -Brian
    jonesbr@ecn.purdue.edu Guest

  2. #2

    Default Re: CRT randomly loses power?

    In comp.os.linux.setup purdue.edu wrote: 

    It sounds like an hardware problem and not a software one. And it
    looks like is located in the CRT itself. Bring it to a tech or
    just buy a new one.

    Davide
    Davide Guest

  3. #3

    Default Re: CRT randomly loses power?

    In message <bo12m2$16rsdu$news.uni-berlin.de>, Davide Bianchi
    <net> writes 
    >
    >It sounds like an hardware problem and not a software one. And it
    >looks like is located in the CRT itself. Bring it to a tech or
    >just buy a new one.
    >[/ref]
    Agreed. If you can use a soldering iron, or know someone who can, the
    best bet is the pins of the CRT socket. The PCB this socket sits in is
    usually large and heavy, carrying all the video circuitry, and along
    with thermal expansion and contraction, this causes the joints to break.

    Needless to say, be exceptionally careful as the high voltages inside a
    monitor do not go away at the moment of switch-off. Unplug it and
    ideally leave it at least overnight, and still be very careful about
    what you touch.

    Yes, I know CRT monitors are fairly cheap, but that isn't the point. By
    far the best way of recycling anything is to keep on using it. Joint
    failure can occur within a couple of years of manufacture, when the
    monitor really has another five years or so of useful life left.
    --
    Joe
    Joe Guest

  4. #4

    Default Re: CRT randomly loses power?

    Davide Bianchi <net> wrote in message news:<bo12m2$16rsdu$news.uni-berlin.de>... 
    >
    > It sounds like an hardware problem and not a software one. And it
    > looks like is located in the CRT itself. Bring it to a tech or
    > just buy a new one.[/ref]

    I already thought of that, but you'll see in my original post that the described
    behavior does _not_ occur under Windows 2000 (it is a dual boot machine).
    Thus, I'm back to thinking that the problem is software related.

     

    Thanks for the reply.

    -Brian
    jonesbr@ecn.purdue.edu Guest

  5. #5

    Default Re: CRT randomly loses power?

    On 1 Nov 2003 14:16:23 -0800, purdue.edu wrote: 
    >
    > I already thought of that, but you'll see in my original post that
    > the described behavior does _not_ occur under Windows 2000 (it is a
    > dual boot machine). Thus, I'm back to thinking that the problem is
    > software related.[/ref]

    Not necessarily...

    I have experienced a problem with bad memory that occurred in only Linux
    (KDE crashed on a memory access error) and not Windows. Replaced the
    memory and my Linux problems went away.

    The two OS's utilize h/w differently. It's possible that Linux is using
    different sync / refresh rates (etc) that trigger the h/w error.

    - W. Citoan
    --
    Military secrets are the most fleeting of all.
    -- Spock, "The Enterprise Incident", stardate 5027.4
    W. Guest

  6. #6

    Default Re: CRT randomly loses power?

    On Sat, 01 Nov 2003 20:59:20 +0000, Joe wrote:
     
    >>
    >>It sounds like an hardware problem and not a software one. And it
    >>looks like is located in the CRT itself. Bring it to a tech or
    >>just buy a new one.
    >>[/ref]
    > Agreed. If you can use a soldering iron, or know someone who can, the
    > best bet is the pins of the CRT socket. The PCB this socket sits in is
    > usually large and heavy, carrying all the video circuitry, and along
    > with thermal expansion and contraction, this causes the joints to break.
    >
    > Needless to say, be exceptionally careful as the high voltages inside a
    > monitor do not go away at the moment of switch-off. Unplug it and
    > ideally leave it at least overnight, and still be very careful about
    > what you touch.
    >
    > Yes, I know CRT monitors are fairly cheap, but that isn't the point. By
    > far the best way of recycling anything is to keep on using it. Joint
    > failure can occur within a couple of years of manufacture, when the
    > monitor really has another five years or so of useful life left.[/ref]

    I'm starting to get one of the colours dropping out every now and again -
    it goes pinkish so I guess it must be the green tube. I'm pretty sure this
    is a fault in or near the plug of the CRT, because it's a new motherboard
    with onboard video, and wiggling the plug and bending the cable seems to
    fix it temporarily.

    I'm thinking that if this goes altogether, I'll try to fix it as follows:

    1. get a suitable 15 pin din plug. (already done this just in case)
    2. cut a short length of the cable sheath off just above the wires.
    3. if the wires are colour coded, go to step 5.
    4. otherwise label them all in some way, putting two labels on each wire
    with a gap between.
    5. Cut all the wires.
    6. Use a circuit tester to work out which wires go to which pins.
    7. Solder up the new plug with the right wires on the right pins. (Not
    forgetting that sneaky gotcha when you remember afterwards that you should
    have slid the plug cover up the cable _before_ you soldered it up.)

    Any comments?

    andy.

    --
    remove 'n-u-l-l' to email me. html mail or attachments will go in the spam
    bin unless notified with [html] or [attachment] in the subject line.
    Andy Guest

  7. #7

    Default Re: CRT randomly loses power?

    Andy Baxter <null.free-online.co.uk> writes:
     

    We had a case at my university a while back with a bunch of new nvidia
    cards. After about a year, the picture started getting fuzzy, with
    streaks and shadows, on about half of the cards.

    --
    Måns Rullgård
    se
    Måns Guest

  8. #8

    Default Re: CRT randomly loses power?

    On Saturday 01 November 2003 14:42 purdue.edu wrote:
     
    Run, don't walk, to your XF86Config file, and change this lines left
    hand figure to something the monitor can tolerate, its apparently too
    low. This results in the scan transistor/transformer getting
    dangerously close to the saturation point at the right hand side of the
    screen, which in turn causes it to draw too much currant and get too
    hot.

    Under the "Monitor" section, find this line:
    HorizSync 27-79
    and raise the left hand number to at least 31.

    If that doesn't help, then I'd suspect that the transistor's heat sink
    compound may be dried out and its getting too hot anyway. Remove it if
    you're familiar with hot soldering irons, clean it up and regrease it,
    and re-install it. If hot metal isn't your cup of tea, get somebody
    else, prefereably someone who can put a "CET" after their name like I
    do and have them do it. And check the condition of the electrolytic
    capacitors in that area also.
     

    --
    Cheers, Gene
    A mostly retired old coot who is a CET.
    root Guest

  9. #9

    Default Re: CRT randomly loses power?

    > > I already thought of that, but you'll see in my original post that 
    >
    > Not necessarily...
    >
    > I have experienced a problem with bad memory that occurred in only Linux
    > (KDE crashed on a memory access error) and not Windows. Replaced the
    > memory and my Linux problems went away.[/ref]

    This I can easily believe. I guess I wasn't expecting a similar
    problem when
    dealing with my monitor because....

     

    ....I automatically probed the monitor to get the settings. (I forget
    what the
    name of the industry spec that allows this is called at the moment.)
    Then I
    compared the resulting XF86Config settings against the listed specs
    at:

    http://www.necmitsubishi.com/products/home/DetailedSpecs.cfm?product_id=199&division=NEC

    The only thing I had to fine tune was the "DisplaySize" option. The
    horizontal and vertical refresh numbers were right on.

     

    Thanks for the response... let me know if you have any more thoughts!

    -Brian
    jonesbr@ecn.purdue.edu Guest

  10. #10

    Default Re: CRT randomly loses power?

    Thanks for the response! My comments inline below...

    root <den> wrote in message news:<vm%ob.24691$gnilink.net>... 
    > Run, don't walk, to your XF86Config file, and change this lines left
    > hand figure to something the monitor can tolerate, its apparently too
    > low. This results in the scan transistor/transformer getting
    > dangerously close to the saturation point at the right hand side of the
    > screen, which in turn causes it to draw too much currant and get too
    > hot.[/ref]

    The explanation has a certain logic, but why the right side?

     

    Unfortunately, I already had my minimum HorizSync set to 31, so this
    isn't the final answer for me. For reference, here is the relevant
    portion
    of my XF86Config:

    Section "Device"
    Identifier "Videocard0"
    Driver "nvidia"
    VendorName "Videocard vendor"
    BoardName "NVIDIA GeForce 4 (generic)"
    VideoRam 65536
    Option "NoLogo" "1"
    Option "RenderAccel" "1"
    Option "WindowFlip" "1"
    Option "Overlay" "1"
    Option "CIOverlay" "1"
    Option "UseEdidFreqs" "1"
    Option "UseClipIDs" "1"
    EndSection

    Section "Monitor"
    Identifier "Monitor0"
    VendorName "NEC"
    ModelName "MultiSync 97F"
    DisplaySize 365.8 274.3
    HorizSync 31.0 - 96.0
    VertRefresh 55.0 - 160.0
    Option "DPMS"
    EndSection

    Section "Screen"
    Identifier "Screen0"
    Device "Videocard0"
    Monitor "Monitor0"
    DefaultDepth 24
    SubSection "Display"
    Depth 24
    Modes "1280x1024" "1280x960" "1152x864" "1024x768"
    "800x600" "640x480"
    EndSubSection
    EndSection


    A detailed description of my monitor (with the rate information)
    can be found at:

    http://www.necmitsubishi.com/products/home/DetailedSpecs.cfm?product_id=199&division=NEC

     

    I'm always looking for an excuse to tinker, but my skills in this area
    are lacking enough that I don't want to risk permanant damage to
    what is not yet a completely dead monitor.

    Thanks again!

    -Brian
    jonesbr@ecn.purdue.edu Guest

  11. #11

    Default Re: CRT randomly loses power?

    In comp.os.linux.help purdue.edu wrote: [/ref]
     

    No logic that I can see. He is saying that going as slow as possible
    (which won't happen since X chooses the fastest config within stated
    limits) comething called a "scan transistor" to get to a "saturation
    point" at the "right hand side".

    I presume he is talking about a driver for the horizontal sweep on the
    beam? If so, I think he is saying that the driver has to pass more
    current to drive the beam further right, and that it can't pass more
    than its maximum (or maybe he is talking about voltage and the
    collector bottoming out above the base .. nah, nobody will drive
    from the collector end, will they? It'll be a darlington follower
    with emitter end following the voltage on the collector of some other
    transistor).

    Why would going slowly increase the voltage or current requirement for a
    given deflection? It wouldn't, on gross physics.

    Maybe he means the beam has to dwell at the right too long? Well,
    adjust your modeline. You can control that precisely. But dwelling too
    long? It'll only make a difference if the fraction of the overall time
    spent there is more! And that is up to you and your modeline.

    Yes, that would make the transistor get hot, but it's the cause, not
    the effect! And getting hot is not good, but will only cause a
    meltdown, and other heat related defects. Nothing repairable.
     [/ref]
     

    Forget it. Even if there were something in it, your Modeline would bot
    be exercising the lower limit of the hscan bounds!
     

    Eh?
     

    Way too high V limits. Take 'em down to something sensible, like 80.
     


    Peter
    P.T. Guest

  12. #12

    Default Re: CRT randomly loses power?

    it.uc3m.es (P.T. Breuer) writes:
     
    >
    > Way too high V limits. Take 'em down to something sensible, like 80.[/ref]

    How is 160 Hz way too high? It's perfectly normal for a monitor to
    support such frequencies. In fact, I have some that do. Only they
    don't support it at high resolutions, since the hsync frequency sets
    the limit there.

    --
    Måns Rullgård
    se
    Måns Guest

  13. #13

    Default Re: CRT randomly loses power?

    In comp.os.linux.hardware M?ns Rullg?rd <se> wrote: 
     
    > >
    > > Way too high V limits. Take 'em down to something sensible, like 80.[/ref][/ref]
     

    Because it's about twice normal. You can't even see flicker over about
    60Hz. By the time you get to 70Hz you've left behind even beat
    frequencies with lighting (50Hz here in europe, 60Hz in the US). VESA
    norms are about 72-75Hz. You can't possibly have any need for any more
    than 80Hz.

     

    No it isn't. Besides that, a monitor does not "support" a vscan rate
    directly. It's an indirect consequence of the number of lines you
    choose to display on the screen, and the hscan frequency you choose.
    The hscan limit is what counts. The vertical travel rate of the beam is
    relatively slow and is not limiting.

    If you only put 100 dots per line, and the max hscan rate is about
    200KHz, and you only have 10 lines per screen, then you will achieve
    some phenomenal vscan rates! But I just say that to illustrate that the
    vscan figure is not directly related to machine limits.

    What you want to consider is what overall refresh rate on the whole
    picture you are comfortable with. Set the limit at that. Then the
    pixel scan rate will be the slowest compatible with your comfortable
    viewing rate (which in turn also depends on pixel latency, and so on).
    Then the beam will dwell the maximum time on each pixel and be
    "brighter". And you will get sharper images because at lower
    pixel frequencies the inevitable bleedoff of high frequencies in the
    beam will be relatively less.
     

    There you are! No, it's not normal. And certainly not normal if human
    beings rather than aliens from outher space are the intended viewers.
     

    It sets it everywhere, being the only mechanical limiting factor.

    Set the vsync at 80, or 85 if you must. 160 is insane,
    counterproductive, and just plain silly.

    Show us the modeline chosen by X for your monitor (do an X -probeonly).


    Peter
    Peter Guest

  14. Moderated Post

    Default Re: CRT randomly loses power?

    Removed by Administrator
    root Guest
    Moderated Post

  15. #15

    Default Re: CRT randomly loses power?

    "Peter T. Breuer" <uc3m.es> writes:
     [/ref]

    >
    > Because it's about twice normal. You can't even see flicker over
    > about 60Hz. By the time you get to 70Hz you've left behind even
    > beat frequencies with lighting (50Hz here in europe, 60Hz in the
    > US). VESA norms are about 72-75Hz. You can't possibly have any need
    > for any more than 80Hz.[/ref]

    With my monitor, I can see flicker at 70 Hz with bright colors. At 75
    Hz I can't see it any more.
     
    >
    > No it isn't. Besides that, a monitor does not "support" a vscan
    > rate directly. It's an indirect consequence of the number of lines
    > you choose to display on the screen, and the hscan frequency you
    > choose. The hscan limit is what counts. The vertical travel rate
    > of the beam is relatively slow and is not limiting.[/ref]

    OK, bad choice of words. Still, there are monitors where vrefresh is
    limited to 90 Hz (or whatever), albeit indirectly. Don't forget that
    the maximum pixel rate is also a monitor limitation.
     
    >
    > There you are! No, it's not normal. And certainly not normal if human
    > beings rather than aliens from outher space are the intended viewers.[/ref]

    Who said I'm not an alien?
     
    >
    > It sets it everywhere, being the only mechanical limiting factor.
    >
    > Set the vsync at 80, or 85 if you must. 160 is insane,
    > counterproductive, and just plain silly.[/ref]

    Perhaps it's silly, but X won't use it either case, being limited by
    hsync range.

    --
    Måns Rullgård
    se
    Måns Guest

  16. #16

    Default Re: CRT randomly loses power?

    In article <se>,
    =?iso-8859-1?q?M=E5ns_Rullg=E5rd?= <se> wrote: 
    > >
    > > Way too high V limits. Take 'em down to something sensible, like 80.[/ref]
    >
    > How is 160 Hz way too high? It's perfectly normal for a monitor to
    > support such frequencies.[/ref]

    I have 120Hz as an upper bound in mine, but the highest rate is
    320x240103Hz, and usually I run 1536x115261Hz (I don't perceive flicker
    very much).
     

    For higher resolutions, sure, as you said; for my 320x240, the horizontal
    rate is 35KHz.

    --
    -eben rIr.OcoPm home.tampabay.rr.com/hactar
    "God does not play dice" -- Einstein
    "Not only does God play dice, he sometimes throws
    them where they can't be seen." -- Stephen Hawking
    Hactar Guest

  17. #17

    Default Re: CRT randomly loses power?


    "Peter T. Breuer" <uc3m.es> wrote in message
    news:117.139.117... 
    > [/ref]

    >
    > Because it's about twice normal. You can't even see flicker over about
    > 60Hz. By the time you get to 70Hz you've left behind even beat
    > frequencies with lighting (50Hz here in europe, 60Hz in the US). VESA
    > norms are about 72-75Hz. You can't possibly have any need for any more
    > than 80Hz.[/ref]

    Sigh. New account, new filters, I'm seeing Peter's snarkiness again.

    I've got plenty of users who claim to see the difference between 60 and
    higher, and a few who can tell if it's 75 cycles and higher. The 60-cycle
    frequency for merging successive visual images is a *nominal* frequency.
    Different people have different tolerances for it, and will happily pay
    quite a lot of money and effort to get it higher if they're one of those
    particularly sensitive to it.

    I'd suggest actually taking some courses in neuro-physiology to understand
    why the 60-cycle thing exists, and why televisions and movie films get by
    with so much less.


    Nico Guest

  18. #18

    Default Re: CRT randomly loses power?

    In comp.os.linux.help Mans Rullgard <se> wrote: 
     
    > > 
    > >
    > > Because it's about twice normal. You can't even see flicker over
    > > about 60Hz. By the time you get to 70Hz you've left behind even
    > > beat frequencies with lighting (50Hz here in europe, 60Hz in the
    > > US). VESA norms are about 72-75Hz. You can't possibly have any need
    > > for any more than 80Hz.[/ref][/ref]
     

    Fantastic. I congratulate you on your eyesight. Wear dark glasses.
    :-).

     
    > >
    > > No it isn't. Besides that, a monitor does not "support" a vscan
    > > rate directly. It's an indirect consequence of the number of lines
    > > you choose to display on the screen, and the hscan frequency you
    > > choose. The hscan limit is what counts. The vertical travel rate
    > > of the beam is relatively slow and is not limiting.[/ref][/ref]
     

    Sure (i.e. "emphatically yes"). But if you are at the max clock, you
    have chosen badly for a modeline. You want to be at the lowest clock
    possible that gives you a refresh rate that you like (as I explained in
    the other post, for reasons of picture brightness and sharpness, not to
    mention stability), and generally speaking "well within monitor limits".
     
    > >
    > > There you are! No, it's not normal. And certainly not normal if human
    > > beings rather than aliens from outer space are the intended viewers.[/ref][/ref]
     

    Sorry. I didn't mean to imply that you weren't :-/.

    Peter
    P.T. Guest

  19. #19

    Default Re: CRT randomly loses power?

    In comp.os.linux.help Nico Kadel-Garcia <net> wrote:
     
    > > 
    > > 
    > >
    > > Because it's about twice normal. You can't even see flicker over about
    > > 60Hz. By the time you get to 70Hz you've left behind even beat
    > > frequencies with lighting (50Hz here in europe, 60Hz in the US). VESA
    > > norms are about 72-75Hz. You can't possibly have any need for any more
    > > than 80Hz.[/ref][/ref]
     

    Nah. The scales have just dropped from your eyes.
     

    Is that relevant to my advice to limit to 80? And in any case, the
    point is that "160 is plain counterproductive and silly". If you wish
    to dispute that, say so. Otherwise, one has to ask "what are YOU
    squeeking about"?
     

    Great. So they can all take my advice.
     

    What is it with you and 60Hz? Even *I* can see flicker at 60Hz - not
    that it worries me. Over 60Hz I certainly can't distinguish it from
    general picture instability, and I have used a lot of monitors over a
    lot of years. At 75Hz I believe myself to be completely happy scanwise,
    but a bad video card will cause wobble that you will confuse for refresh
    awareness at whatever frequency you run at, and every video card becomes
    bad at higher frequencies. So I have learned always to favour a lower
    pixel clock over a few Hz higher vscan. That's the sum of it.

    I'm not sure why tvs get by with less. Something with motion sensing,
    I guess.

    Peter
    P.T. Guest

  20. #20

    Default Re: CRT randomly loses power?

    it.uc3m.es (P.T. Breuer) writes:
     
    >
    > Fantastic. I congratulate you on your eyesight. Wear dark glasses.[/ref]

    Well, the maximum flicker frequency I can see varies with monitors. I
    suppose the decay rate of the phosphor varies. With this particular
    monitor, I can barely notice a flicker at 70 Hz, if there are large
    areas of white or bright colors. Thought I don't see what the dark
    glasses have to do with this.

    --
    Måns Rullgård
    se
    Måns Guest

Page 1 of 2 12 LastLast

Similar Threads

  1. PDF graphic loses gradients
    By rainbow@adobeforums.com in forum Adobe Acrobat Macintosh
    Replies: 4
    Last Post: December 13th, 01:43 PM
  2. OS X loses USB ADSL Modem
    By Pascal Sartoretti in forum Mac Networking
    Replies: 0
    Last Post: October 9th, 07:21 PM
  3. Graphire 2 pen loses sensitivity
    By Chris Cox in forum Adobe Photoshop 7, CS, CS2 & CS3
    Replies: 2
    Last Post: July 10th, 05:32 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139