Realtek HD Sound Card "invisible"

Hi there

System:
HP Pavillion a6030.za Desktop
CPU: AMD Dual Core 3600+ 1.9ghz
GFX: nVidia 8500gt
OS: Windows 7 Ultimate x64 Service Pack 1

It has an onboard Realtek HD Audio Sound Card, not sure exactly what model as tireless searching on the internet has turned up nothing.

Ok so my friend(This is his computer) left a movie paused in Windows Media Player and went to the shop. When he returned his computer was off. When he rebooted, he had a choice from Safe Mode Normal etc, he chose normal and after windows loaded no errors had shown up.
He noticed he had no sound. So i came over to see why.
In "Playback Devices" recording etc nothing was showing. Not a single device, the speakers were plugged in and on, I even changed ports and speakers. I went to device manager and his sound card was not on the list. I performed a hardware scan and nothing showed up(The sound and game controller section wasnt even on the list in hardware manager). I then proceded to find the driver through searching on the HP support site. Obviously the add new hardware manager did not work as there was no hardware to be found, according to windows. I used the "Add Legacy Hardware" function to install the driver. During installs the computer kept giving a BsoD. I went through every different model and manufacturer available(All realtek ofcourse), making sure to uninstall the failed driver afterwards each time. All to no avail and many BsoD restarts. I checked eventviewer and nothing suspicious happened around the time the computer switched off solo. Except a report on windows not being shutdown properly recently.
To the computer the sound card is non existent. The sound card is enabled in the BioS.
I have run through every troubleshooting I can except placing a seperate sound card in a PCI slot to see if it works as there are none available and all the shops are closed.
Is this a known windows problem?

I have also performed a few system restores and to no avail either

Any help as soon as possible would be greatly appreciated.
Thanks in advance

MORE INFO I THINK MIGHT HELP:
He just plugged his xbox controller in, drivers were installed a few days ago already, and its not functioning either. So it seems the Sound, Game Controller section of hardware is not functioning.
All devices linked to that section seem to be non existent

Did you make sure when you enabled intergrated devices in BIOS that you did save settings?