Crosshair IV Formula Manual voltage still auto

What CPU cooler are you running? Not this will make a diff, just curious as you don't have one listed.

Are you OCing in the bios? Never use a utility to OC.

1.475v Vcore seems very high for a 3.8GHz OC, most can achieve a 4.0GHz with only 1.39-1.41v for vcore.

Here is a list of basic bios settings that may help you.

These are settings that I use with bios version 1304 and are not the only options available, but are used by many others with good results. They should also be fine for the 1902 bios as well. One option I have not worked with is the D.O.C.P (Dram Over Clock Profile) and if your Dram is an issue I’d encourage it’s use.
Ai Overclock Tuner – Manual
AMD Turbo Core – Disable (not applicable with all CPU’s)
PCIE Freq – 100
Dram Freq – Manually enter factory spec
Dram Timing Configuration – Manually enter factory timing specs
PWM Phase Control – Full Phase
CPU Voltage OCP – Enabled
CPU PWM Freq - Auto
CPU Load Line Calibration – Full - be sure and watch load voltage
CPU/NB LLC – Full - be sure and watch load voltage
CPU/NB Voltage OCP – Enabled
Extreme OV – Disabled
CPU & NB Voltage Mode – Offset or Manual, using Offset Voltage allows use of Cool & Quiet up to a multiplier of 18x. (I encourage Offset Mode)
CPU VDDA voltage – Auto
Dram Voltage – Manually enter factory spec
HT Voltage – usually auto is fine for a 4.0GHz
NB Voltage – usually auto is fine for 4.0GHz if you have a BE CPU. Non BE CPU’s may require additional volts as this is for the chipset which may need an increase when going past 260MHz CPU Bus Freq. (stock is 1.11, max around 1.3v. I have seen this as high as 1.5v in extreme cases for long periods of time.
NB 1.8v – auto
CPU Spread Spectrum – Disabled for stability
PCIE Spread Spectrum – Disabled for stability
Be sure to manually enter a value for both CPU Voltage and CPU/NB Voltage (not auto)
All other settings can stay at default or auto for most cases.

If I can be of any more help just send me a PM.

You may want to come and join us in the link in my sig (ASUS Crosshair IV Formula/Extreme Club) where you'll find many other CHIV owners as well as several links on the OP which might also give you some help.