specially blended

Hi! Just upgraded to Windows 7 Permium Home (clean install after wiping HD). I had Vista before and I did have sound then (which was just yesterday). Under 7 I have no sound, which is so annoying. I have a 32bit, Packard Bell, Intel Core 2.4GHz, 4GB. Don't know the sound card off the top of my head, but I thought that the newer versions (Vista and 7) detected that automatically anyhow? Speakers are not muted, rather volume is cracked up to 11!! :cool: What to do?? I know its a difficult problem, but what to do next? Greetings!!