|Well, if you've tried everything then anything we suggest will be redundant since you have already tried it.|
Of course you could give us details of exactly what you have tried so we can then tell if you really have tried everything.
You have not even said whether the system is laptop or desktop, whether you are using internal or external speakers, whether it has onboard sound or a discrete soundcard, Whether sound ever worked, Whether the lack of sound followed a fresh install of the operating system or some other event. In fact you have provided no useful information on which to base an effective answer. We know only two things It's a Dell and might be running XP.
Goin' Fishin' (Some day)