I assume you swapped over the power cables for the PSU?
That would suggest that you've blown a fuse.
Check what fuse your PSU should have in its power cable or you'll keep having this problem.
Also, COP could be artifacting due to a bug of some sort, either graphics drivers, the game's coding or COP is simply more demanding?
You should try more than just those 3 games, you'll get a better idea of the issue if you do.
That would suggest that you've blown a fuse.
Check what fuse your PSU should have in its power cable or you'll keep having this problem.
Also, COP could be artifacting due to a bug of some sort, either graphics drivers, the game's coding or COP is simply more demanding?
You should try more than just those 3 games, you'll get a better idea of the issue if you do.