Hi M,
I think that since you got the XP CD from another Compaq laptop that it may have some drivers that are unique to that model (if ever each of these laptops differ in model).
At the moment, check with DEVICE MANAGER. If you see any marks in Device Manager, try reinstalling ALL the drivers for your model.
My suggestion is do a fresh install. Get hold of a retail XP CD. D/load and install all related drivers for your model from Compaq website.
http://h20000.www2.hp.com/bizsupport...&swEnvOID=1093