Will not boot? You mean the screen wont show the post and loading but you have power? White lines usually mean dead LCD, could be mobo but I'd try a LCD replacement and ribbon cable first. If you could elaborate more maybe we could expand our troubleshooting.
If you can't boot into safe mode, then it is probably a hardware issue. Since you didn't provide any details I can only suggest stripping your PC down to the minimum needed to boot and see what happens. If you can use alternative known working parts that makes it easier to eliminate motherboard problems.