System Specs Are: windows xp home, 512mb ram, 2.8GHz intel celeron cpu

The sound on my computer has completely gone. the volume icon is missing. I have an

onboard Realtek AC97 sound device.
All of a sudden, the other day i swithed on the pc and no sound. device manager reports no

audio problems, however system information says that IRQ 16 is being used by a graphics

controller and usb universal host controller. in control panel under sounds and audio

devices i get a "no audio device" message. the last two programs i installed are windows

media player 11 and IE 7.0 about two weeks ago, and the problem starter yesterday.
i have tried system restore to no avail. BIOS sound is enabled. speakers work just fine on

another pc. i can't Extract a copy of Sndvol32.exe from windows xp cd because all i have

are the three restore cd's when i bought the pc, and when i try to reinstall audio drivers

via the restore cd or from C:\Drivers\Audio\OriginalDriver the system stops installing at

80% and i get the following:"Realteck ac'97 audio (4.86) tool for driver update has

encountered a problem and needs to close."
i tried unistalling realtek ac'97 in add/remove programs but i get the following pop up:
realtek ac'97 audio
>setupDLL\setupDLL.cpp (391)
pAPP:Realtek ac'97 audio
PVENDOR:Realtek semiconductor corp.
PGUID:fb08f381-6533-4108-b7dd-039e11fbc27e
$11.50.0.42618
@windows XP service pack 2 (2600) IE 7.0.5700.6
Setup has experienced an error.
Please do the following:
- Close any running programs
- Empty your temporary folder
- Check your internet connection (Internet-based Setups)
error code 5001

when i run directX diagnostic tool i get the following:
Sound Tab 1: DirectSound test results: Failure at step 3 (DirectSoundCreate): HRESULT =

0x8878000a (The request failed because DirectSound resources, such as the priority level,

were already in use by another caller.) and
Music Tab: DirectMusic test results: Failure at step 6 (Activating the IDirectMusicPort):

HRESULT = 0x8878000a (The request failed because DirectSound resources, such as the

priority level, were already in use by another caller.)

device manager shows the following under sound, video and game controllers:
audio codecs, legacy audio drivers, legacy video capture drivers, media control devices,
and video codecs. each device is enabled and supposedly "working properly".

when i installed a pci sound card the volum icon does come back and i can hear music, but

i'd like to figure out the audio problem.
i know i can do a windows xp re-install but that is going to be my last option.
what do you guys think?

As to the last option: re-installing XP is usually the main source of losing Audio drivers.

What is the make and model of the computer or if custom built the motherboard?

Point being that windows does not have these drivers.

Going to your computer manufacturer's web site under Support | Downloads | Drivers | Audio is the best source.

If custom built go to your motherboard manufacturer's site.

If you need assistance please post back the IDs of computer or motherboard.

i have an e-machines T2895 and have tried to download the latest audio drivers from the makers website but the machine will not let me, the system stops installing at 80% and i get the following:"Realteck ac'97 audio (4.86) tool for driver update has encountered a problem and needs to close." also, i can't uninstall Realtek ac'97 from add/remove programs.

could this be a case where i might have to (flash) or update the motherboard drivers? i have read where this can be potentially dangerous.

also, i have not yet tried to re-install windows xp.