I assume that your cooler is a Corsair H100i
Your OC is all dependant on your temperatures and your CPU.
I would suggest you start with XMP profile as your mode of overclock in the BIOS
Then set your multi to 42x
And then down to the vCore set 1.260 if you can boot to OS then good.
Run RealBench or some other short stress test with CPUz and HWmonitor open. You can download them from the web no problem.
Make a note of your temps under load and the voltage when your CPU is loaded.
That would be a good place to start.
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