PBG4 Screen Dimness

[unitethenations]

Hi macrumors members,
I have a PBG4 whose screen brightness is quite abysmal, to the point of eye strain. I'm going to take it to an apple store to have it checked out. I phoned tech support and they told me that it would have to be assessed (as to whether they'd replace the screen).

My question:
I've already had 2 hardware failures (hdd) and a burned adapter in the past year. If they determine that the screen should be replaced (under applecare) will they just give me a new computer since this would make it about 3 major failures plus the adapter problem? Will they likely even have PBG4 screens in stock?

 

[Philscbx]

For example on mine when I have cinema display attached and screen brightness controls up, I have to lower cinema brightness almost all the way to match the brightness on high on the powerbook.

Oddly though, when I'm in darken room with just the powerbook, it appears too bright on high.

I guess these older powerbooks do degrade after some time. 3 years now.
The Cinema display is fairly unused but the same age.

I don't know how to measure brightness other than comparing light values using my digital camera taking light readings with a set lens, f/stop and iso.
Maybe there are other tools out there.

I dought a new computer will happen.
I've had everything replaced minus screen and hard drive in the last year.