So, after installing Windows 7 I found that my on board sound card didn't work. There simply weren't drivers for it. I friend had an old PCI Sound Blaster Audigy 2 kicking about that he was kind enough to give me.
I slapped it in, fired up the computer and once Windows 7 was booted up it found some new hardware. The initial installation failed, but when I ran Windows Update and checked for new updates it found:
Creative Audigy Audio Processor (WDM)
After installing the updates and restarting the computer it worked!