Title: The frequency of the monitor
Question: How to get the frequency of the monitor...
Answer:
uses
Windows, SysUtils;
...
// This function returns the display frequency in Hz.
function GetDisplayFrequency: Integer;
var
DeviceMode: TDeviceMode;
begin
EnumDisplaySettings(nil, Cardinal(-1), DeviceMode);
Result := DeviceMode.dmDisplayFrequency;
end;