laptop replacement screen issues

Replacing a Dell Inspiron 5000e laptop screen. On boot, the screen lights up for a second, makes a high-pitched peep, and fades to almost nothing. This same action occurrs on two separate 5000's (same screen). Works fine with an external monitor. Works fine with a different screen. Tried turning off all hardware acceleration, dropped display settings all the way down, safe mode, even tried entering the bios-- no change.

Anyone have any ideas??

Thank you!!