First, you need to stop trying to force it with vcore. Once you've gone over 1.32v, and it won't even boot at 4.5, then it has nothing to do with vcore. It's either another setting or you have a bad board. Have you been able to boot at 4.0, 4.1, 4.2 etc? If so, at what vcore? Have you tried to enable Internal PLL overvolting? although you shouldn't need to enable it at that speed, but you never know.
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