Hi,
It may be just software problem. Try to delete some windows updates from past days when you discovered that game is crashing. Had this problem with some games.
And if you ran tests to stress cpu and gpu and nothing happened then it is sure that problems are software related. If you have not run it yet, do it to rule out hardware problems.
HX750 is OP PSU for your PC and unless it has some production flaw it should not be a problem.
Best regards