Hi misa360, Here's a documentation of various easy ways to reinstall OS on your R420. downloads.dell.com/.../ms-win-srvr-2008-r2_Reference%20Guide2_en-us.pdf 
what is the best way to reformat a poweredge R420 server? I have never reformatted a server before, so I would love to know what the best way to do it is.  Thank you in advance...
reformatting Dell Poweredge R420