Dell forum: Dell Inspiron 1420 brightness issue

I've been looking everywhere trying to fix a similar problem. Though as far back as I can remember the screen has always darkened when the laptop is unplugged. I have a Dell Inspiron 1520 w/Windows Vista from 2007. My computer is plenty old enough for the ccfl tubes to be dying. The only thing that makes me wonder is my friend has the same model and does NOT have the same problem. She does have a glossy screen instead of an anti-glare screen like me but I believe they are both lcd right? I still have my original 9-cell battery as well but I rarely use the laptop without plugging it in since the screen is too dark without it. I know it has nothing to do with my settings since they are all on full brightness. I need to decide if I need a new battery or a new screen since both are somewhat expensive. Any ideas?

P.S. - I've been offered to have a new computer as my graduation gift but I'm reluctant because we just upgraded the RAM and Hard drive space and I've kept it in pretty good condition. Do you think it's worth it to scrap it and start over?

Well I really don't think a screen shot is necessary but if you need verification that I know my settings, very well: No matter what path you take to get there, you have to go to "Power Options" on Vista. Under "Power Options" I have it set on "High Performance" which should use full brightness even w/out being plugged in. But since that made no change I also went to "Adjust the display brightness" and set it to the max brightness with or without being plugged in. When that made no difference, I went to "Change advanced power settings" and under "Display" I made sure brightness was set to "100%" whether on battery or plugged in. It is possible that it's a glitch that ignores my settings but it is definitely not the settings I put in that are the problem.

And when I said "As far back as I can remember" I mean exactly that which doesn't mean this problem was always there just that I can't remember how far back it started. I'd love to know if a new battery would do the trick but I don't want to spend $80 and find out it's not the battery at all.

I didn't add the screen shot mostly because I don't know how to add it without a place to put the attachment. IF you could tell me, I have the file saved already. And I wanted to take it up with Dell but honestly my laziness in dealing with the problem has left me out of warranty and, as I understand it, you can't use their tech support without being under warranty. I don't mind them saying they won't fix it because I know it's my fault I let the warranty run out but I just want to know what the problem is. Thanks.
-Lauren

You are missing a VGA driver. I have the same problem. On the Dell website, you can download the driver for other models but they don't exist for the 1420.

http://support.dell.com/support/downloads/driverslist.aspx?c=us&l=en&s=gen&ServiceTag=&SystemID=INS_PNT_PM_1420&os=WLH&osl=en&catid=&impid=

this issue has been haunting for a year now and thanks for your information i'm able to do my work while plugged in or using battery with desired brightness.. no longer stuck at a very dim screen when plugged in..thank you so much..you made my day