audio and graphics drop out URGENT!!!

[P Stephen]

I started experiencing audio drop outs and hesitation on the graphics after I upgraded. I since have installed the prior version and am still having the same problem. After the song plays for about 45 seconds to a minute, my screen goes black and audio drops, briefly. If I click the mouse, the screen reappears. I have a dell laptop and have never had this problem until now. I have 3 gigs, this week. Two are new ones and I don't want to lose them. Please help ASAP.
Thanks in Advance