Mac OS 9 Lives

Mac OS 9 Discussion => Hardware => Topic started by: DrNo7 on October 31, 2023, 11:40:31 PM

Title: Uneven backlight on PowerBook 12
Post by: DrNo7 on October 31, 2023, 11:40:31 PM
Hi everybody,

My trusty old Powerbook 12 (1.5GHz) is still kicking bytes butts but I noticed when powering it up few days ago a slightly darker area mid-bottom that felt like the backlight was uneven (I will try to take a pic to illustrate).
Is there any known symptoms like these? And if yes, how bad of a surgery would it mean (as these baby are not the simplest to take apart)?

Thanks in advance for your insight :)
Title: Re: Uneven backlight on PowerBook 12
Post by: ssp3 on November 01, 2023, 01:34:38 AM
Those CCFL backlight tubes fade sooner or later. That's in their nature. I have several PB G4s with dark-ish/uneven/colored displays.

Here's someone replacing CCFL tube in TiBook:
https://forums.macrumors.com/threads/my-titanium-powerbook-g4-repairs-continued.2283655/post-29604820

But, I would rather look for complete display assembly from PB with failed GPU chip than try to disassemble it.
Title: Re: Uneven backlight on PowerBook 12
Post by: DrNo7 on November 02, 2023, 10:38:09 PM
Thank you very much for the link ssp3 !

Definitely, the surgery down to and then inside the display assembly is a bit much for my taste (at least while it is mostly a cosmetic issue). And changing the display assembly is slightly "simpler" but will be prone to the same result.

Surprisingly, the post you linked mentions the exact situation I describe:
Quote
17. There is a dark spot in the center of the panel... At this stage I dismantled things again to reseat the backlight channel. When I pulled it out I could see a portion of the reflective material inside the channel was folded over itself, so I was able to gently pry it back out.

But if it is, I cannot explain what could have warped the reflective material (and again it is a long way inside to straighten it out). I will hope it stabilizes like this for the foreseeable future and will prepare myself for the (literal) dark times ahead :p