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purplegrain · Jul 14, 2006, 12:44 PM

Hi all,

After two years of using my PowerBook 17'' - 1,33 Ghz without a problem, I now have awful vertical solid lines of 1px (and 1px distance from each other) all the way down on the display, which affect only specific colours.

Recently the display developed those vertical lines everywhere where there was a black colour! The lines are solid blue and 1px thick, with 1px distance. When I move the black picture around the lines move as well, so it is not a fixed position on the display.

On external monitor everything is fine! All hardware tests show no problem and re-sets don't improve the issue.

The effect began re-appearing every time after ca 20 min of using the PB. When PB is cold and starting up, even now, the display is fine for few minutes, then it goes wrong. Lately the same effect started appearing also on the red colour (pink lines) and green colour (light green lines). Also blue pixelated shades appear around windows.

Although no warranty (2 years old), I went to a Apple certified service (in Bulgaria) to find out the cause. They opened it and think it's the display cable, although it could be the display matrix as well (they say). No visible issues inside. Apparently, one cannot order only the display cable (unless second hand), but has to change the whole display.

Questions:
Do you guys think it could be the cable only? How come only specific colours are affected? Can the cable "see" the colours? Is it not likely to be some computations and electronics involved?

Thanks for your valuable comments

ibook_steve · Jul 14, 2006, 03:23 PM

It could possibly be the LVDS cable to the panel, but if it always happens after the machine is warmed up and not when moving the display back and forth indicating damage to the cable, then I'd say your graphics chip is on the blink. The strange part is that you are not seeing it on an external display, but that could just mean the digital interface of the chip is messed up while the analog VGA is fine. Hate to say it, but this looks like a board replacement.

Steve

purplegrain · Jul 14, 2006, 05:15 PM

Hey Steve, thanks a lot for reply. I have always been careful with my PB and on the outside it looks like new. No dropping etc. There is no change when I move screen back-forth. Intuitively, I also think it's not just the cable. I could try post some pictures tomorrow. It looks like a digital issue. What is weird is that the effect begins always ca. 10px to the right of a colour region, not from the first pixel. So, if I had a black square the vertical lines would not begin from the very first left pixel of that square, but from the ca 10th pixel to the right. The first left ca. 10 pixels will always be solid and CORRECT colour (eg black). From 10th pixel onwards I get the blue lines. Same for the red and green colour.
By now I think the lines never disappear, even when the PB is cold...

Something is wrong.

Can I not change only the video card? Why the whole board?

ibook_steve · Jul 14, 2006, 05:38 PM

Because the graphics chip is soldered to the motherboard. Everybody calls it a graphics "card" but there are no separate cards, at least in portables from Apple in at least the past 6 years. Cards require connectors, infrastructure, and most importantly height that don't lend themselves to the possibility of a 1 inch thick computer.

Steve

purplegrain · Jul 15, 2006, 02:16 AM

Thanks Steve,
Any idea how I could test if it's the video chip? Hardware-tests all pass well. Should they not detect something...? Thanks again. On the other hand, it seems temperature-dependent and would the LCD cable be temperature-affected... When PB is really cold, it's fine for ca 10-20 mins, although recently it starts appearing quicker and quicker...

urrl78 · Jul 15, 2006, 06:45 AM

Mine was intermittant, sometimes at startup it would look fine. I sent it in 3 times during the last days of its one year warranty. I believe they replaced the display cable but after 3 times of unsuccessful repair they replaced my 1 Ghz 17" with a 1.5 Ghz 17" model brand new. They never found the cause on the old 1 Ghz 17".

harrisjamieh · Jul 15, 2006, 07:27 AM

Does this have any relation to the vertical lines on the MacBooks after 10.4.7?
http://forums.macnn.com/showthread.php?t=300464

just an idea...

harrisjamieh · Jul 15, 2006, 07:27 AM

Grrr.. double post

purplegrain · Jul 15, 2006, 12:36 PM

It doesn't make a difference which OS I install. I tried that few times without improvement.

I really wouldn't like my PB to be severely damaged after only 2 years. My old Pismo also developed screen problems just few weeks after warranty... :-( Apple seems to have an issue with screens. By those prices I would wish to be able to use my laptop for 3 years at least not less. What is a laptop without a screen?

eevyl · Jul 16, 2006, 05:54 AM

If the problem does not appear in the external monitor, it's not an issue with the video card/chip. Seems like an issue with the screen/cable, as you were told by the tech support.

purplegrain · Jul 16, 2006, 07:37 AM

Originally Posted by eevyl

If the problem does not appear in the external monitor, it's not an issue with the video card/chip. Seems like an issue with the screen/cable, as you were told by the tech support.

Thanks again, but what about the temperature issue? Would the cable be affected by temperature like that? It seems when the PB is totally cold it works for ca 10-20 mins until it heats up, then the display goes all wrong. Thanks.

purplegrain · 12:44 PM

It is all so weird. Now it seems to me there must be something on the chip, because it really depends on the colours. If my screen is filled with black colour, I have lines everywhere, but if there is a lighter colour, they disappear. This cannot be the cable, since there is no logic that it can "see" the colours displayed. But since the picture is all fine on an external monitor, I am very puzzled what it could be.