Are you using the latest BIOS? If not please update using Qflash or DOS. Then once you've updated enter the BIOS and load optimized defaults, then save/apply/reboot BACK to the BIOS. Once in the BIOS again set your SATA settings, memory voltage, and anything else you need to set, then save/apply/reboot and try to load windows.
If you can't even boot with that card, you may need to do that with an older card, then shut down and install the new card and try again