HP Compaq Presario C500t Notebook "c571nr" Questions

I have a compaq presario C571NR notebook laptop and installed windows Xp professional but there is no sound/audio device is the message anytime i want to play music with it. please help me out!  

...every time i try to use it with a messenger, it does not work. i have a compaq presario t2080 model c571nr, with windows vista. when in yahoo messenger go to actions then call setup, this will set ...

sound drivers for presario c500 ther is no sound I just got the sound in C500. Use the C571NR drivers. http://h10025.www1.hp.com/ewfrf/wc/softwareList?os=228&lc=en&cc=us&dlc=en&product=3441641&lang=en

I have a compaq presario C571NR and I am trying to replace the CMOS battery,i've removed the case and pulled the PCB up to reveal the battery but i can't for the life of me figure out how to get the ...