That's high for 5.1. Set your loadline to mode4, and vcore to 1.31v, and try that. That should give you roughly 1.29v under load. Remember that vDroop is healthy; you want some droop to cover the transient spikes that occur when load increases/decreases and voltage fluctuates.
Set VCCIO and VCCSA to 1.19 and 1.20. I can run 4133 on those voltages so you should be fine with your XMP settings at those IO/SA voltages, even if you have a weaker IMC.
Of course, do the cpu voltage, test, and then do the IO/SA settings together. Don't pull a KAC and change 3 things at once and then not be able to tell what caused the crash
1.35v under load is a lot for a 240/280 rad, and is a lot for a simple 5.1.