How to Check your Dell Warranty
http://support.dell.com/support/topics/global.aspx/support/warranty/warr...?
And enter your service tag information into the form. It will tell you how long you have left on your warranty.
If the machine is still covered by a warranty, you can contact DoIT Installation and Repair and they'll work on it and replace hardware for free.
Here's how to contact DoIT Installation and Repair.