Solar EMP - Three key facts.

1.   We can expect a few hours notice of an ElectroMagnetic Pulse but can't expect to be spared.
2.   The electrical grid is most at risk, not your computer.  Most power transformers will fail on the exposed side of the earth when we get another Carrington event.
3.   Large transformers need to be ordered about three years in advance and the US will depend on imports initially.

Link at Future Pundit: Devastating consequences for the electric power grid.

More than a hundred wheels, making 20 miles a day.
Overhead wires must be taken down to allow the transformer to pass.