I have now solved the problem for my Surface:
Solution 1 - With the latest Intel drivers: Deactivate the internal Surface Screen and set the external Screen to Master Screen -> no blackouts but you can't use the internal Screen.
Solution 2 - Delete the current graphics drivers and go back to Intel Driver Version 21.20.16.4678 https://downloadcenter.intel.com/download/26836 after deleting the current drivers with the device manager and make sure that windows will not update them again. -> No Blackouts but you have old drivers.
I think the problem comes from the combination of the latest surface firmware update an the latest intel graphics drivers.