New mobo/PSU: Need to format HD?

I'll be upgrading my Mobo and PSU next week. I recently did a complete format/reinstall of my HD and all applications, and would like to avoid doing this again if possible.

Is there any reason why when I upgrade my Mobo and PSU I would need to re-install the OS etc?

As far as I know there is no Motherboard-specific software 'installed' on the hard drive, the BIOS being the only thing it really uses (except for maybe some Mobo specific software overclocking). It this going to be as simple as I think?

In case it's useful, I'm upgrading to the MSI 800FSB and 2.4C CPU, from a Gigabyte 1394 board with 2.4B.

Well, the PSU switch requires nothing of course. But, you do have mobo related software. Every mobo needs .inf device drivers installed and that puts the configuration into the Windows registry. Your mobo will have an install CD that has this stuff on it. What Windows does is to installl generic drivers at first until you update to better drivers. Yes, it's best to reinstall Windows. It's also possible to do it without reinstalling, but it can be a hassle.

just reformat... prevents all that residual conflicts and such

Thanks

Thanks fellas, I understand it better now. I didn't realise
that Windows is genuinly aware of the motherboard itself. But of courwe the Mobo has built-in features and ports etc that all use device drivers, it makes sense for me to start clean.

I don't fully trust the built-in update/transfer facility, so I guess I'll back up all files (MP3s etc) to CD for transfer.

Thanks again.