ASrock 890GX Extreme3

[arroyo]

I'm done. I cannot get more than 3500MHz on my 1055T.

My actual and stable settings are:
Cpu Frequency: 250MHz
CPU Multiplier: x14
CPU Clock: 3500MHz
CPU Voltage: 1.4V
NB Multiplier: x9 (2250MHz)
CPU-NB voltage: 1.35V
HT Multiplier: x8 (2000MHz)
Memory Clock 3/8: 1333MHz (8-8-8-24 2T)
Memory Voltage: 1.63V
CPU VDDA: 2.7V

I've tried on bios 2.50 and 2.42B. I've tried rising CPU-NB and Vcore voltage up to 1.45V and still cannot go past 3500MHz stable. I'm testing stability using Linx. Cooling is not a problem because CPU temperature is always under 55 degrees (hwmonitor). PSU is not the problem because it's powerfull Seasonic M12-D 850W. Memory is Adata 1600 Plus and it goes up to 1600MHz on CPU multiplier x10.

So what can be the problem with stability >3500MHz ? Any help ?