The "Dell Premium Panel Guarantee" only applies to Bright sub-pixel defects. Bright sub-pixel defects only appear on a full black windows desktop background. The policy does not apply to Dark (stuck/fixed/dead) sub-pixel defects which appear on non-black windows desktop backgrounds.
We do not validate our monitors in a dark room. We validate our monitors in rooms with a minimum of 150 lux which is standard office lighting.
* Change the windows desktop background to all black* If you see a stuck pixel that is white, red, green, or blue, that means it is a Bright sub-pixel defect* Change the windows desktop background to all white* If you see a pixel that is black or colored, it is called a Dark sub-pixel defect
Sometimes you can "exercise" a pixel to un-stick it
* Download/save smartUDPixel.exe to your windows desktop* Turn off all Windows power management and screen savers* Run the software* Click and drag the blinking box to cover the pixel* Let it run for 15 minutes
* Download/save montest.exe to your windows desktop* Turn off all Windows power management and screen savers* Run the software* Press F9* Let it run for 15 minutes* Press Esc* Press Enter/Return to exit
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