I had just reinstalled windows xp pro. and when I did it my sound wasnt there anymore. this has happend before when I reinstalled windows I need to know how to figure out what sound card I have with out opening up my computer?

1: Consult computer documention. It should tell you what sound card you have.
2: If no documention then you either have to open and look at system hareware or if on-board sound then you can note the bios string that appears on the lower left of your monitor screen during bootup. Press the Pause/Break key to freeze screen long enough to write the bios string down. Repost with bios id and we can figure out what motherboard/soundchip you have.

Note: When asking for help, you must include some information. Otherwise we don't have a clue what pc or sound system you have. :)

:)