First of all...you should use a blog!

Second of all...restart your computer a couple of times. I've lost my sound a lot back then and restarting my computer helped. If not....I don't know.

Second of all...restart your computer a couple of times.

..done it, a couple of times...

and sorry i dont know this one must belong to my blog

Hmmm.....I'm not sure then. Maybe someone else can help you.

Maybe you havent installed your speaker or something?

You should check your sound settings under the control panel.

Obviously, when you formatted your computer ,the sound card driver has gone also and I'm sure that you have no clue about what's the brand/name of your sound card.

Install this software:
http://www.download.com/Everest-Ulti...-10499291.html

-It will tell you what drivers you need for your computer.
-Choose the sound section [I DUNNO WHERE, JUST LOOK FOR IT ]
-Copy the name of the driver or write it down.
-GOOGLE IT , THEN DOWNLOAD IT!

and be careful next time.

Good tip.