I HAVE NO SOUND

I reinstalled the whole system of my Gateway Notebook, Model MX6436. Now, I cant find the drivers for audio, and the modem. I actually cannot find out the name of the audio and the modem devices, as they are not installed, and so cannot figure out...

Ok.. So I Have a Windows XP Home edition Gateway Laptop (Model : MX6436) And i just recently reinstalled my laptop so now theres nothing i asked my friend to help me get some stuff back i dont know what he got me back but everything is working ...