What does the sub card do on the A20m?

[SaberX]

Just wanted to know?
It's seems that the 14.1" screen on my thinkpad is a bit dark.
Has that something to do with the sub card?

[slagmi]

More likely the age of the display panel itself
Replacing the inverter is worth a shot and won't cost big bucks.
I figure if the sub card was bad you wouldn't get a display at all- not even to an external monitor.

[SaberX]

The inverter has to made for the 14'1" screen right?
I have another A20m here with a 12'1" screen.Will the inverter on the 12'1 fit a 14.1?
I never dont replaced one befot and figgered i'd ask here first befor i tear apart the two thinkpads.

[slagmi]

Well...yes
Though it's really more of a question of will it fit in the space provided and is the physical plug compatible- and you're OK there
Seems to me some of them used the exact same inverter...
Easy enough to find out- What's the Model/Type of each Thinkpad?

[SaberX]

I have an A20m 2628-14u(the good working unit) 12.1"
and an A21m 2628-Gwu(with a bad system board)14'1"
On the A20m i have put the 14.1"screen(in place of the 12".
I have syitched the inverters and worked great now it 's a little bit brighter.
Thanks.
I also switched the celeron for the P-III 800 but only showing up as 650mhz.I think it's do to my A20m with the celeron was not set up for SpeedStepting and runs the cpu in a lower setting.