I'm having the exact same problem as http://en.community.dell.com/support-forums/laptop/f/3519/t/20004345 who reported: "I have been experiencing distorted color while trying to watch certain videos online. For example if I want to watch [a video] the thumb nail and video advertisements are in color, but the video content from this and other sites plays in black and white or only in very [washed out] colors. Even more confusing is the fact that this only occurs while my laptop is connected to the AC adapter. If the computer is unplugged the color returns to normal then goes back to black and white when the charger is reconnected."
I'm using the factory AC adapter, plugged into the wall. I've tried updating "AMD Radeon R5" video drivers to no avail.
The problem started the day after warranty expired - I kid you not :[
Hi there, have you tried updating the BIOS? It might be worth a shot, here is a direct link (as long as the model is 5755). For a more direct list of updates you can also enter your Service Tag here and have the files manually listed.