Hello:
if you use SYSPREP prior to removing your hard drive you will not need to reinstall nor reformat for windows / I have done this many times / you will however need to load all drivers as needed for any of your PCI slot componets , chipset drivers for your mobo / the standard stuff !!
here is a link you may want to read (this process is very painless) / enjoy
http://www.hardforum.com/showthread.php?t=772307
regards
joe