I recently went through the trauma of a motherboard upgrade with Windows XP installed so I thought I would share.... I was running WinXP Pro Sp1 before upgrading and took the precaution of backing up my whole computer to another hard disk using Ghost. After replacement of the motherboard and putting everything together I booted up and was greeted by the "blue screen of death" with an incomprehensible message. But I was wise to this...apparently it happens whenever an upgrade includes a different IDE Controller and according to the MS Knowledge Base is fixed by doing what they call an "in place upgrade". This involves booting from the original CD and working through to the Repair option. Did that and WinXP fired up seemingly OK except that I then had to work through the re-activation trauma for each of WinXP, OfficeXP, PublisherXP, Frontpage XP etc etc. Then I realised that some of my latest hardware drivers had reverted to the original, rather poor, generic drivers that came with WinXP, which was a nuisance, but more importantly, I had lost my two Internet Connections and the Internet Connection Wizard didn't work. Nothing seemed to fix the problem but I fortunately was still able to connect via my Win98 dual boot. Restoring the settings I had just before upgrading just threw me back into the "blue screen of death". Had just about resigned myself to a long search of the internet and/or costly support calls when I realised that I hadn't reinstalled the XP Sp1 patch yet. Did that and all drivers and internet connections came right! The Sp1 patch must make some radical alterations to your settings!