все, разобрался
$mapelements.="<div style='float:left; position:relative; left:".($x*50)."; top:".($y*50)."; width:50px; height:50px; background-color:#CCCCCC' id='x".$x."y".$y."'></div>";
<td align="left" valign="top" bgcolor="#FFFFCC"><div style='float:left; position:relative; left:0; top:0; width:600px; height:600px;'><?php echo $mapelements;?></div></td>