Altere o conteúdo com base em uma seleção suspensa de um banco de dados mysql

function myUpdateFunc()
{
  
  
  var mySelected = $("#CPU").find("option:selected").val();
  $('#divResults').html ('selected value :' + mySelected)
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<form id="parts">
        <fieldset>
            <legend>Choose your parts</legend>
            Any parts marked with * are required<br/><br/>
            <label for="CPU">CPU*</label><br/>
            
                <select id="CPU" name="CPU" onchange="myUpdateFunc()">
                <option value="" disabled selected>Select your Part</option>
                <option value="1">value 1</option>
                <option value="2">value 2</option>
                </select>
                <br/>

               <div id="divResults"/>

                <br/><br/>