My old mobo died, i bought a new one and swapped it. Plugged my old Harddrive and fired it up. I get a POST screen, the Windows logo ... and then the system restarts.
I also had this problem. I suspected it was due to either Windows licencing (Windows does not like it if your hardware has changed drastically) or, more probably, wrong drivers. I suspected the latter because it was crashing, instead of giving me an error.
I fixed it by re-installing Windows.
What i suggest is to backup all your important files, and re-install Windows.
It's because of the wrong drivers. Your Windows installation has adapted itself to your previous motherboard and has drivers set up for your harddrive controllers, chipsets, etc and you just tried to boot up with something entirely different. Use the repair function from the cdrom or simply do a reinstall.