Welcome to the forums xMrAx

. I've replaced the motherboard on a system - from a P35 to P55 chipset IIRC, still sticking with an Intel chipset which may have smoothed the transition. Normally I'd have done a fresh install, but I was helping a friend and needed to get the system up and running ASAP to get data from it.
If you don't want to re-install the OS, you could always give it a try and see how it goes - it should work, even if it may be more optimal to go from a fresh install (it will try and install most new drivers on the first boot if it can). Just be 100% sure you've got the data backed up already so you've got nothing to lose - as there's still a chance that the switchover doesn't go down well. You may have more problems if your IDE/SATA controller changes and you may need to re-activate Windows.