Do you have BIOS V23.1 and what is your power supply? I also have the MSI 990XA-GD55. I see the voltages change to and it does not bother me, I think it's just the nature of power distribution and how the circuits respond to different loads and states.
additional components include: AMD FX-8350 cpu, G.Skill sniper cl9 1866 ram, MSI Radeon HD 7850 oc graphics, corsair cx600 power suppply and corsair h80i water cooling.
I think my highest BIOS voltage is 1.446V and passes prime95 and IntelBurnTest at 4.4GHz.
I've run it at 4.6GHz and 1.446V and failed the stability tests but play Battlefield 3 and do video encoding with no problems.
I've overclocked to 4.6 and 4.7Ghz and tested stability and done well but had to use AMD overdrive, or MSI control center to access higher voltages (~1.49V)
I think the BIOS will need to be improved and they are holding back on the voltage so we don't quickly burn out our cpu's with +1.6 to 1.75V
My 4.7GHz OC ==> http://i.imgur.com/0AmCYP7.jpgEdited by xtoocoolx - 3/18/13 at 11:48pm