No Sound driver installed  

ok try these SoundMAX ADI1988 Audio Driver version 6.10.1.6270 at Alpha Downloads :)

NyaX said:

See below screenShot:

Are you rebooting after each install?

are you 100% certain the sound card is ok and not faulty ? have you right clicked on the multimedia adaptor (with the yellow exclamation mark) and selected update driver ?

I dunno, I would have thought the Vista driver from your models support page would have worked, but obviously not. Have you tried the drivers Pebbly posted?

NyaX said:

Yeah.. i downloaded that one twice.. But It says one file is missing.

there should be 29 files in the link i posted how many have you got , there has got to be something wrong here with your setup if you cannot load a driver in compat mode and you have missing files

Try this driver in compatibility mode - ADI SoundMAX audio driver - ThinkCentre A52 (type 8327)