The original cd drive in my Presario 7222 no longer will read cds. The owners manal I got is on a cd so my info is limited. How hard would it be to replace the original cd with a newer one? Where can I find some detailed info before attempting since Compaq claims they never test third party stuff in their products. I have replaced the modem and added memory before which is about my experience to date working inside the machine. Thanks for any advice or direction.