function loadXMLDoc(tabname)
{
	
if (window.XMLHttpRequest)
  {// code for IE7+, Firefox, Chrome, Opera, Safari
  xmlhttp=new XMLHttpRequest();
  }
else
  {// code for IE6, IE5
  xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
  }
  document.getElementById('test').innerHTML='<div style="background-color:#ECEAED; padding-left:250px; width:350px; height:50px; border:1px solid #D5D5D5"><img style="padding-top:10px;" src="http://www.laptopreviews.org.uk/wp-content/themes/revolution_news-21/images/homepageload.gif" /></div>';  
  url = "http://www.laptopreviews.org.uk/wp-content/themes/revolution_news-21/ajax_tab.php?tabname="+tabname;
xmlhttp.open("GET",url,false);
xmlhttp.send(null);
document.getElementById('test').innerHTML=xmlhttp.responseText;
}
function tabbutton(iid)
{
document.getElementById('b1').className = 'off';
document.getElementById('b2').className = 'off';
document.getElementById('b3').className = 'off';
document.getElementById('b4').className = 'off';
document.getElementById(iid).className = 'on';
}