Question Is 1.56V high for OCed Xeon X5450?

[yullbarez]

I've overclocked my X5450 to 3753 MHz. But can only stable at 1.56 V. I'm don't understand that many people can go higher with less voltage same model my mobo. My mobo is Asus ROG Commando P965. I think bsod could be causing by RAMs cuz they running at stock voltage at 826 MHz only 26 MHz difference. That high Voltage causing overheating the CPU. Many people can go further with giving less voltage than i gave same mobo model that's the only thing what i'm don't understand.
PC Specs:
CPU : Intel Xeon X5450 3.75 GHz OC @ 1.56V

Mobo: Asus ROG Commando
RAM :8GB (2GBx4) Kingston DDR2 800 MHz CL6 GPU : Asus GTX 780 Ti Directcu II OC 3GB GDDR5 384 Bit (Running at stock)
CPU Cooler : Cooler Master MA410M RGB HDD1: Samsung HD155UI 1.5 TB 5400 RPM HDD2: Samsung HD250HJ 250 GB 7200 RPM OS: Windows 10 Pro 64-Bit 1809
PSU: Corsair VS650 650 W 80+ Bronze
Thanks for the comments.

 

[RememberThe5th]

Ram can take 2.1V without issue, try 5-5-5-15 timings (not sure if 1T or 2T), or 5-5-5-18 or 6-6-6-18.
Take lowest divider you can set.
For chipset voltage aka north bridge Im not sure. You're gonna have to look up what they used.
You can try lower the multiplier and getting higher FSB.