Hp laptop screens on dell laptops

I have found that most HP laptop screens, I've experimented with the 15.4" ones, can be connected to dell laptops which sort of take the same connector on the back, but the backlight behavior is weird. Some of these HP screens will light up very dim on all settings, and some will light up dim then bright then dimmer and brighter as you try to adjust brightness.

Some dell laptop screens from Inspiron 1521, 1525, 1520 are all compatible with each other, just replace the whole thing with the inverter included. Inspiron 1521 and 1520 also use the same screen cables. Have the same screen chassis, hinges, etc. The ones with the webcam are plug and play.