I have 2 old hard drives in my PC's that seem to have lead-based solder on the circuit boards, and i have a fan that i duct-taped on the hard drive for cooling. I dunno if i have to take the fans off, or is it not that big of a deal. According to MSN.com, that stuff is serious, but i don't really care, especially that people used to use lead everywhere, like in paint and gas. It took like 50 years to find out that it's bad for health. I forgot to mention that my PC's are running with the outside of the case taken off for better cooling.