No sound when windows XP was reinstalled

Hello,

My laptop recently conked out and I took it to a repair place to have it fixed. Since I was primarily concerned with getting the internet working for work, I really didn't use the media features until two weeks later in another country. Now, I've realized there's no sound on it, nor has there been since I got it back. When I look at the sound devices, it says "no audio device" under volume. How do I fix this? I'm using windows XP and it's an old ASUS computer but I'm not exactly sure what model it is.