realtek high definition audio code 10 error..help??

Hi,
My volume icon is gone and when i checked the sound devices it says no sound devices found.Everything is greyed out.Had uninstalled realtek and high defi audio and restarted but yet not much has been done! have followed the other threads and still dosent work..(my windows aint genuine)..Cant roll back to system restore as i had forgotten to set a restore point...and worst of all i lost my motherboard cd..and not sure which mother board i have..aint much of a technical person..Again, Realtek High Definition Audio shows up in the list at the end of the wizard with a yellow circle and an " ! " inside that circle..when checked device manager..Have lost all hope..tried followinf from other threads but well..still no sound
all this has been done:
Is the Windows Audio service running?
Go to Control Panel>Administrative Tools>Services
Scroll down the list of services until you find the Windows Audio service.
Right click on it and choose Properties.
Make sure it is set to Automatic and Start is checked.
BIOS sound must be enabled for on-board sound... Disabled for an add-on card
..uninstalled thge drivers and ran cc cleaner..did regedit stuff..:-(
My system details:

Main board:
Bus Clock: 200 megahertz
BIOS: American Megatrends Inc. 080015 03/29/2008

Operating system:
Windows XP Professional Service Pack 2 (build 2600)
Install Language: English (United States)
System Locale: English (United States)

Drives:
80.02 Gigabytes Usable Hard Drive Capacity
12.77 Gigabytes Hard Drive Free Space

HL-DT-ST DVD-RAM GH22NP20 [Optical drive]
3.5" format removeable media [Floppy drive]

WDC WD800BD-22MRA1 [Hard drive] (80.03 GB) -- drive 0, s/n WD-WMAM9CEU4078, rev 10.01E01, SMART Status: Healthy

Display:
NVIDIA GeForce 7050 / NVIDIA nForce 610i [Display adapter]
Proview 15.7 [Monitor] (15.7"vis, s/n 109121213181, October 2006)
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