When replace motherboard; reformat boot drive?

[htspecialist]

I have finally given up on the MSI K8N Neo 4 Platinum SLI motherboard and going to replace it with one from ASUS. Do I need to reformat the old motherboards boot drive and do a clean install or can I just use the origional boot drive witout reformatting? I would hate to have to reformat the original boot drive and loose Windows XP originally installed on it and then get tagged for a new windows install.