I've been building my own for 25 years & have swapped Motherboards & kept exsisting OS on HD's a few times.
This can go smooth or be a little more complicated & just takes a bit more work.
Depending on how you have your HD setup in IDE or Raid Mode is important, along with chipset drivers.
A different Mobo will have different chipset drivers & Bios won't be setup for Raid.
Chipset drivers will need to be uninstalled in device manager. If you see they don't uninstall properly in Windows,try doing it in safe mode. Make sure you set your HD mode in new Mobo Bios properly. Windows will auto install IDE mode drivers.
Raid drivers are different for different chipsets,so you need to uninstall & Reinstall the correct Raid Driver for the new Chipset in Safe mode before allowing the new Mobo to boot all the way into windows or you may get a BSOD.
It's best to remove all existing drivers unless your going to transfer the same sound card & not install the Mobo IC sound driver. Lan/Raid/CPU/USB/NIC drivers will be different for the new Mobo chipset. You should be able to install all the drivers from the Mobo CD or may have to go to Mobo driver downloads for correct Raid driver & save it on a USB drive so you can install it in safe mode. This is a must do using a Mobo with a UEFI Bios. I have worked with other Mobo's without a UEFI Bios & have seen correct Raid drivers get installed auto. I like the click Bios features on my new MSI 990FXA-GD 80 V2 Mobo. There is a flaw in Win 7 Ultimate 64 bit OS. When installing a fresh copy of it with a UEFI Bios setup for Raid,you will get promped that the Hard Drive/CDrom needs a drive letter. This is incorrect, What it's really looking for are the Raid drivers for the HD if you set the Bios for it & will need to install them using a USB drive after downloding them from the MSI Global download page.. I spoke to the Tech Reps at MSI about this prompt & they know it's a flaw & don't know why it asks you for an HD/CDrom drive letter.. We all know, nobody's perfect, not even Microsoft.
I wrote this just for all that visit this website. Hope I shared something valuable with you. Good Luck