I've had a Google on this and it looks like there is a way to do this and several people have had success. However, there is also a fair chance of stuffing the laptop completely so I'm not going to give you that information - You'll have to find it for yourself. The correct way is to call Dell support and get the laptop re-registered in your name. They will need the serial number and service tag, which should be marked on the machine. They will then check if the machine is on their 'stolen' list. If they are happy, they can generate a one-time password from the service tag number which you can use to access the BIOS and set your own password.