Realtek High Definition Audio not recognized on Windows 7
Overall, old drivers like Windows XP drivers are well supported on Windows 7. But as usual, not everything goes always as planned.
In this case I had to fix a not working sound card. To be more specific, it was a Realtek High Definition Audio onboard sound card. The card was just not recognized by Windows 7, while it did when I was running XP on that same machine. And this was was very strange.
My situation was fixed with a really simple fix. You might try the following:
1. Start your computer and enter your BIOS by directly pressing F1 (or F10 or any other key depending on your machine)
2. Go to the advanced menu or somewhere where you can see Onboard Audio.
3. You might now have 3 options to choose. Disabled, Enabled and Automatic.
4. If it is set on Automatic then change it to Enabled and start Windows as usual.
5. If you’re lucky Windows might now recognize the driver and even directly install it. 
If it the above doesn’t work for you:
- Try my alternative solution here.
- You can try installing the driver by downloading the Realtek HD Audio driver for Windows 7 from the official site.
- In some cases you might also necesseraly need to install the chipset drivers for your motherboard.
- You can also try deleting the current audio drivers and reinstalling them.
Related posts:
- Azalia/AC’97 High Definition Audio Driver Windows 7
- Internet 1500 Laser Cordless Desktop drivers and software
- Windows 7 Login Error “The referenced account is currently locked out and may not be logged on to”
Ty mate, this really helped me step 1 through 4