Hi,
I'm with Dell's online outreach program. I saw your post and thought I'd stop by to see if I can be of help.
When you were checking the power settings did you try to download the newest driver for that system from our support site,
http://support.Dell.com ? If you pull up that site there is a link for drivers and downloads and you can use your service tag (located on a sticker attached to the bottom of the system) to filter the downloads so you only get those appropriate for your model.
It's possible that the driver has been corrupted and isn't loading correctly. That would be my first suggestion to try, if you haven't.
It's also possible that the LCD cable in the system isn't seated correctly, but I'm not sure that is the cause. You can also take a look at the user manuals on our support site to see how to replace LCDs on that system, and it will show you how to access the LCD display cable. You can check it to make sure it's fully connected.
Let me know if any of this helps, or if you have any other questions. I'll stop back later to see if I can help further.
Thank you,
Todd
Customer Advocate
Dell, Inc.
http://direct2dell.com/one2one/archi...1/19/3648.aspx