Does it POST, can you get to BIOS?
If yes, I would try re-syncing the primary/secondary BIOS. This will be ALT+F10 or ALT+F12
You can also try to invoke boot from the back up BIOS using the following:
1. Shut off the power supply using the switch on the back of the PSU, wait 10-15 seconds.
2. Press and hold the case Power On switch, then while still holding turn on the power supply from the switch on the rear.
3. Still holding the case power on switch, the board will start, once it does release the case power on switch and shut off the power supply via the switch on the read of the unit. (Do the latter two parts as quickly as you can once the board starts)
4. The board will shut down.
5. Turn the power supply back on using the switch on the rear of the unit.
6. Turn on the motherboard by pressing the case power on button.
If the above doesn't help, I would try to re-flash the BIOS again using QFlash if possible, or USB. @BIOS is not reliable (or very safe) and of course useless if you can't get to windows.