Why does my notebook screen go dark after a few minutes online?

The screen on my m1710 goes dark (down to brightness 4 from 8) after I use my notebook for around 10 minutes. A little while later it will go back to brightness 8 then to 4 again. It takes a few minutes between switching from bright to dark and vice versa. During this time the notebook is plugged into the wall and I am just browsing the internet or watching a movie.

Any ideas?

So far the only thing I did was turn off the computer and disconnect and reconnect the notebook's LCD. The problem still persists.

 

My first thought would be an inverter problem (the inverter provides power to the backlight). However, that normally gives you a black screen. Does the M1710 have dual lamps? If so, it could be a problem with one lamp.

Or is that change in brightness as if you were manually changing the brightness via the keyboard?

John

 

I'm not sure about how many inverters I have. I think there are two, but I could be mistaken. Any easy way to check?

I also tried the keyboard but there is no change in brightness (either brighter or darker).

 

The display removal guide only shows one inverter. However, there might be different display versions. You might be able to look carefully around the edges and see where the light is coming from for both full and half brightness.

John

 

Just looked at the link you provided. Hopefully I can fix this with a $20 inverter from ebay. Anyone know if I can get this part from Dell directly?

 

Have you tried going into control panel, and modifying the power options?
Sometimes you can set the brightness level to decrease when you are not active on the system.

K-TRON

 

Yeah like K-tron says it sounds like power saving mode if it's when you're watching movies (M$ does not consider that active) or light browsing.

Does it happen after keyboard inactivity basically?

Either way try adjusting your power save mode to 30mins or 1 hr as the minimum for everything and then see what happens. Also there are often monitor powersaving settings in the BIOS of the laptop too, check those as well.

If it still persists, that's when I'd start breaking out the hardware solutions.

 

I looked through the control panel and all of my settings have the screen at full brightness when the computer is plugged in. During the times the screen turned off I was using the computer to browse the internet and later to play World of Warcraft. The strange thing is it would be bright for a few minutes, then dark for a few minutes and then bright again and so on. There was no keyboard inactivity.

Could this be from my new nVidia drivers? I am using vista x64 169.12 drivers from laptopvideo2go.com. (I just reformatted and upgraded to Vista Ultimate x64 last week; I didn't have these problems under 32bit Home Prem.)

 

Well then that's not power saving mode if it's while you're using the keyboard and such.

It could be a driver issue or even potentially a hardware one. Best to do some trouble shooting (at some point try another driver or role back to your previous setup), and if it persists, if it's still under warranty have someone look at it.