High definition audio device driver Microsoft - emachines

Hello,
I have an e-machines computer. I recently uninstalled windows xp and then installed windows vista. I have no sound now. I have monsoon speakers. The computer says no audio output device is installed. Under the device manager I receive a code 10 error saying the device can't start. I have a Windows High Definition audio device by Microsoft. I have reinstalled the driver after uninstalling it with what I believe is the correct driver - a Realtek High definition audio device. It all looks the same. Does anyone know why the sound doesn't work yet and how I can get it to work?