Faint diagonal lines via PC Input / VGA

Discussion in 'LCD & LED LCD TVs Forum' started by gaz2785, Mar 26, 2006.

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  1. gaz2785

    gaz2785
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    Recently I have connected my LCD TV to my laptop via a VGA cable.

    I have downloaded some high definition clips and I'm really pleased with the quality.

    One thing however. There appears to be very faint diagonal lines running across the screen. These are most noticable on a black background.

    The manual talks about adjusting the PC Sampling and PC Clock settings to get rid of horizontal and vertical lines. Changing these settings makes no difference and these lines are diagonal, not horizontal or vertical.

    The lines seem like interferance, but I have no other devices switched on nearby (other than the laptop).

    The cable is a 1.5m cable I got with a computer and flat panel monitor, so it's probably not the best quality. Could it really be the cable at fault?

    I'd like to get rid of the lines if possible, however I must admit they are extremely faint and perhaps only someone as pedantic as me would notice them :lesson:
     
  2. gaz2785

    gaz2785
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    Anyone?
     
  3. Bluestraw

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    Suggest you try another cable and see if that makes a difference!
     
  4. David Mackenzie

    David Mackenzie
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    That is weird, have you tried video cable, screen resolution or output device? Just to help nail down the problem./
     
  5. gaz2785

    gaz2785
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    Not sure what you mean. I have used a VGA cable and several different screen resolutions on the laptop.
     
  6. David Mackenzie

    David Mackenzie
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    Do you have any other cables or computers to try?
     
  7. gaz2785

    gaz2785
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    Not really. I have another computer but it's not a laptop, so lugging the computer into the lounge is not particularly easy.

    The cable came free with a £299 computer + flat screen monitor so it's probably not a very good one. However I only linked it up to test out the high-def clips, so spending £15 - £20 for a new cable would be quite an expensive test :mad:

    I assume it is most likely the cable or computer at fault, rather than the TV?
     
  8. RockySpieler

    RockySpieler
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    What make/model of LCD TV??

    With the different resolutions you have tried, have you tried sending a native resolution (usually 1366x768 for a 32")?

    Are you changing refresh rate to 60Hz?
     
  9. gaz2785

    gaz2785
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    TV is Toshiba 32WL56.

    Refresh rate is set to 60Hz.

    I have tried 800x600, 1024x768, 1280x960 and 1280x1024.

    I don't have 1366x768 available on the computer. All resolutions have the faint diagonal lines.
     
  10. RockySpieler

    RockySpieler
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    Try "reversing" the VGA cable.

    Also try disconnecting all scart's and TV aerial.

    1024x768 should be the best resolution to try given your options.

    Is the cable ok when you use it on your PC with flat panel monitor?

    Check for power leads running close to VGA cable.

    Do you have a surge protector?

    Are you tried running the laptop off batteries, or off mains transformer?
     
  11. gaz2785

    gaz2785
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    Thanks for your suggestions. The lead is currently at my office so I'll bring it home tomorrow night.

    Yes the picture is fine when connected to the flat panel monitor, however it is only a 15 inch screen (the computer monitor) so not sure if that would make a difference. Again I'm wondering if you only need a crappy lead to send the signal to such a small screen, but as I said above I don't really want to spend £20 on a new cable for the sake of a simple test.

    I'll try everything you mentioned above and post the outcome here.

    Thanks again,
     
  12. RockySpieler

    RockySpieler
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    Oh yeah...........if you are really serious about hi-fi and AV you have to turn off your fridge freezer..........but I don't like warm beer!!!!:D

    Good Luck!
     
  13. gaz2785

    gaz2785
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    I tried my girlfriend's desktop computer (using the same cable) and the lines were gone. Her computer looks fantastic on the LCD, but unfortunately isn't able to play HD clips for some reason.

    Anyway, that would narrow the lines down to the laptop rather than the cable or the TV.

    Many thanks,
     
  14. M12YSF

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    I have a toshiba 32WLT66 and I had the same problem with my hitachi DVD / Freeview combo. funnily enough i saw the diagonal lines during freeview display but not during DVD playback... and they both come from the same device??? so not the cable at fault then but perhaps the device. fre view via the TV's built in digital tuner is perfect.

    thanks
     

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