desktop pc?

thanks Astrophel..every thing is onboard..nvidia gf 7100/nf 630i...realtec audio..High speed adsl connection...I have the system running but still no audio..and still only bios defaults..if I try ANY bios changes ..just shuts down and reloads defaults..Intel core 2 duo e8500..Asus p5n-em hdmi m/b if this helps.
no overclocking !!