Most models will alllow ONE TIME CHANGE in bios if the service tag field is blank. HOWEVER only Authorized Dell techs can issue a service tag. We can point you to drivers if you can tell us what the Dell Part Number of the board is but you will NEVER get a service tag for a raw board.  Service tag and System Serial number are the same number.  
Hi guys,I have recently purchased a motherboard off eBay, extracted from a Dell system for a good price. After overcoming all obstacles coming with such a decision I am facing one last hurdle. I started the system and even before I reach BIOS, the motherboard is asking me for a service tag. As far as I understand it, it is normally to be found on the bottom of a Dell device but since I only bought the component, there is no device where I could find it. I did some research and guys there said I only have one shot and if I mess it up, it'd have to be fixed by a professional, something I want to avoid at all costs.Can anyone please advise? Thanks!
eBay, Dell motherboard, service tag number?