system
Given the following post, respond as if you're commenting on Reddit:
human
Does a computer monitor consume energy at different levels depending on the color of the items being displayed?

Basically, I'm wondering if a monitor displaying bright, white colors most of the time will consume more energy than one displaying mostly dark colors. Assuming all else being equal, of course.
gpt
To a first approximation, the answer is that it doesn't matter. Almost all modern computer monitors consist of a liquid-crystal display in front of a white backlight (either LED or fluorescent). Each pixel of the display has transparent electrodes on the front and back, and when an electric field is applied, the pixel changes from transparent to opaque. But very little current actually flows through the liquid crystal itself. Almost all of the power is consumed by the backlight, which is always on.

One major caveat: these days, some monitors have a dynamic contrast feature, which adjusts the brightness of the backlight based on the overall average brightness of the image. So with that feature turned on, a dark image would consume less power. (This isn't primarily motivated by power savings, though. The liquid crystal can't become 100% opaque, so if you try to display a dark image in front of a bright backlight, it looks kind of washed-out. Dimming the backlight improves the apparent contrast a bit.)

Higher-end OLED monitors work differently: instead of a backlight, they have a separate LED for each subpixel of the display. OLEDs have a much better contrast ratio, but they're more expensive to manufacture. On one of those monitors, displaying a pure-black image should consume virtually no power at all.