Auto brightness/contract on new XPS?

I have an XPS 15 with the full-hd screen. I have done a clean Win7 install and have installed the latest intel and nvidia drivers (from Dell). When I'm browsing the web, I notice the screen dim and brighten very slightly as if it was adjusting for contrast or brightness based on the webpage I'm viewing.

I'm not talking about the auto dimming power management feature. I have that disabled. When I'm on a very dark website, I notice the screen dim in the same way as my projector's auto contrast settings make it dim, to boost contrast levels. Then, when I switch tabs to a white background website, I see the brightness go back up. It's not just websites either, but it adjusts based on what is on the screen (like dark vs. light desktop backgrounds for instance). It's very subtle, but definitely noticeable. At first, I attributed it to the lighting in the room, but I've had it for a few weeks now and have noticed it a lot.

It doesn't bother me at all, as I said, its very subtle and the adjustment fades up or down to whatever brightness level it goes to, so its not like BAM in your face, but very gradual (over a 2 second transition period). I'm just surprised that this might be an unlisted feature or there may be a light sensor built in somewhere that nobody has mentioned.

Anybody notice what I'm talking about?

 

I highly doubt that there is a light sensor in the model. Can you let me know what the model no. of the screen is? Mine is AUO17ED.

 

The behavior is definitely based on what is being displayed on the screen and if it is light or dark. You're right, its probably not a light sensor though.

Same screen, btw.

 

I have the 17 inch L701x and just noticed this today for the first time.....freaked me out.....i wish we could get some confirmation on what exactly is handling this.....a piece of dell software?? I think not because i removed most of it.....I don't notice any ambient sensor.....

 

(obviously -- sig) I've got a 14" I think I've experienced what you all have as well, i thought my screen was dying when I first noticed it

 

I had the exact same problem. I solved it by setting the Power Plan to Maximum Performance (for both plugged in and battery mode) in the Intel Graphics and Media Control Panel (found in the Windows control Panel).

This did the trick for me.

 

I noticed this problem today while using the laptop on battery. After digging, I found the solution.

On the graphics properties of Intel graphics, select Power, then Power features, select battery from the drop down menu, and disable "Display Power Saving Technology".

This will fix it.

Hope someone finds this useful.

 

they have this feature on a lot of cellphones (Android based) - image content is analyzed, color brightness, etc and screen brightness is adjusted to save power. interesting to see they're using this on computers now...

the way I noticed it works is darker images dim the screen, and lighter ones pump up the brightness.

 

Thank you SO MUCH!