Azmoore, If the system you had was using the on board graphics prior to fitting the Pci-e graphics card. And none was fitted to the Pci-e slot.
Remove the 770 Ti card.
Plug the monitor cable into the graphics port out put of the board.
Let the computer post and enter the bios.
From there look for the graphics options, there will be a list of what device to initialize as the primary default graphics output device, This should be set to Pci-e or Peg.
If you can turn the on board graphics chip set off do so.
Save the settings in the bios, and exit.
Power the system off and re connect the 770 Ti card and all it power feeds it requires.
And the monitor cable back to the 770 Ti card as well.
Then restart the system.
Let me know if it works when entering the bios and does not freeze.
I think it may resolve the problem, but let me know if it works.
I think the lock up is because the Pci-e slot has to be set first in the bios and the fact it needs to know what the default graphics output device is.
I don`t think it`s a power problem on thinking about it now but a case of the board having a conflict between On board graphics and the 770 ti fitted to the pci-e slot of the board. It should with luck resolve the lock up and freeze.