I have a HP compaq NW8240, and today when I tried to turn it on, it wouldn't power on. That is it turns on for a second, the fan starts and then it knocks off. After trying to start it 5 or 6 times, it starts to smell a little. Not very strong but it smells a bit. Like something could be burning slightly. I have tried it with a universal power supply and the same thing happens. I haven't used the battery in it for ages, and always just used it from the power supply. Any ideas?