xploit

I am currently running windows XP on my system (specs are Asus A7V8X motherboard, 1 gig DDR ram, 2800xp processor and a 9600pro graphics card) but occasionaly getting the "blue screen of death" come up saying an error has ocured from winacusb.sys - i then have to restart my computer. Anyone know why this is happening? Any information greatfully accepted :D thanks