These boards have been removed from mostly new MONITORS with broken screens and should work if properly installed. DELL P3421W MONITOR SUPPLY BOARD 5E50302001 / 4H.50302.A00. Please verify that your board part number is the same as 5E50302001 / 4H.50302.A00. The part number is the first number left of the /, or the sole number listed. Most often written in title as (part number / board number)