That depends on the mainboard. If you are changing chipsets and/or processor types ... format and reinstall. If the chipset is the same, you might get away with it. But the OS will probably require reactivation, as this is not like changing out a CD-ROM for a DVD-ROM.
Personally, when swapping out 'boards, I start over from scratch, to insure stability. I'd rather reinstall than troubleshoot errors ... it's less time-consuming.
In any case, you should remove anything related to the old mainboard in the Device Manager before making the change, and boot into Safe Mode the first time, so that only Windows drivers are loaded, and nothing else. Then you should uninstall any ghosted devices in the Device Manager, and afterwards, try a normal boot. Hopefully, Windows will allow the switch. But don't switch platforms and expect good results. And back up your data ... first. Always back up the data, if nothing else.
Toey
<A HREF="http://forums.btvillarin.com/index.php?act=ST&f=41&t=328&s=91c282f2e5207e99b7a652ee13b3512a" target="_new"><font color=green>My System Rigs</font color=green></A>
___________________________________________
<A HREF="http://forums.btvillarin.com/" target="_new"><b><font color=purple>BTVILLARIN.com</font color=purple></b></A> - <i><font color=orange>Your Computer Questions Answered</font color=orange></i>