Just a thought, when I saw your question :
Have you tried to make a string with all the HTML-code needed for these DD-boxes and then printing the final string? Like this :
<?php
$output = "";
for($x=0; $x<100; $x++) {
$output .= "dropdownbox nr. $x<br>\n";
}
echo $output;
?>
I'm not sure if it would speed up the process of making and showing all those DD-boxes, but you could give it a try.
Oh, and 80 or more form-elements are a lot of elements I think!