Question CPU-Z says Core voltage 1.456V but AIDA 64 says voltage 1.2375V

[yullbarez]

I've overclocked my Xeon X5450 with auto VCore voltage because when i increase voltage little bit system won't boot. After stability test i've checked CPU-Z it says voltage is 1.456V i'm shocked. Then i've check it with AIDA 64 it says 1.2375V it's my stock voltage. Is that problem causing by auto voltage setting?
BIOS Settings:
AI Tuning [Manual]
CPU Frequency [386]
DRAM Frequency [DDR2-772MHz]
PCI Express Frequency [100]
PCI Clock Synchronization [Auto]
Spread Spectrum [Disabled]
CPU VCore Voltage [Auto] (it works at 1.2375 V)
FSB Termination Voltage [Auto]
NB VCore [Auto]
Memory Voltahe [1.800V]
DDRII Cannel A REF Voltage [Auto]
DDRII Cannel B REF Voltage [Auto]
DDRII Controller REF Voltage [Auto]
SB VCore(SATA,PCIE) [Auto]
SB Chipset Voltage [Auto]
Asus C.G.I [Disable]
Static Read Control [Disable]
Configure DRAM Timing by SPD [enable]
CPU Configuration:
CPU Ratio Setting [09.0]
C1E Support [Disabled]
Max CPUID Value Limit [Disabled]
Vanderpool Technology [Disabled]
CPU TM Function [Disabled]
Execute Disable Bit [Enable]
SpeedStep [Disable]
There are my bios settings. Is something wrong on bios settings i'll change it.
System Specs:
Intel Xeon X5450 CPU
Asus ROG Commando P965 Chipset Mobo
AMD FirePro V5800 1GB GDDR5 128 Bit GPU
Kingston (4x2gb) 8GB DDR2 800 MHz CL6 RAM
HDD1: Samsung HD155UI 1.5 TB
HDD2: Samsung HD250HJ 250 GB
HDD3: Samsung SP0411N 40 GB
PSU: SilverStone Strider 500W 80+ Bronze
OS: Windows 10 Pro 64-Bit 1809

 

[scout_03]

what voltage does bios give for cpu .

 

[yullbarez]

what voltage does bios give for cpu .

1.2375V

 

[scout_03]

this is your cpu voltages but to overclock will start to apply xmp on ram then raise the cpu multiplier without touching the voltages on this on .

 

[Karadjgne]

And you are positive everything you are reading is vcore and not VID? There's a difference. VID is the voltage that the cpu asks from the mobo, vcore is what it actually uses. To keep temps down, VID should not be much above vcore. If you have VID set high, that's what the VRM's will supply, no matter what the cpu actually needs. Often happens with Auto settings to guarantee stability.

MSI version of cpu-z reads VID. Asus ROG version of cpu-z reads vcore. Had to look close to see the difference.