That's the bit you're going to be having problems with...
$query5 ="INSERT INTO hardware ('dept_id', 'room_id', 'equiptype', ... etc... , 'present')
VALUES('','$departmentid','$roomid','$equiptmenttype','$serialnumber','$suppilername', '$price', '$present')";
mysql_query($query5) or die(mysql_error());
I've setup the code as an example as you haven't listed the tables column headers/labels so you need to edit the
('dept_id', 'room_id', 'equiptype', ... etc... , 'present')
It'll also provide you with an error as to why it didn't like it which is good debugging practice.
The suggestion re: the dots, etc... isn't necessary as you're using double quotes to enclose the $query5 string.. You would need to if you were using single quotes.