I've got a 3 year old lap top and the charger is on the fritz. I had a break in the line a while back and soldered it and shrink wrapped it and its worked fine for about 4 months, but now i'm hearing it arc some where in the charger so i think i am going to stop using it. I bought a charger off woot a month ago, and woot claimed it would work on my HP dv 4000, but the specs don't match. My battery calls for 18.5 V 3.5A ( 65 W) and the charger's out put is 19 V 4.74 A (90 W). I would have assumed woot was jsut mistaken about this charger working for my laptop, but several other sites have the same specs on replacement chargers for my laptop. My question is do laptops have some sort of current limter? If it does would the huge difference in current, cause it to dissipate a ton of heat, and eventually burn up?