Mobo Overvolting on its own

[Osmium]

Hey guys, longtime member here but I've been inactive for a year or two.

 

I've been having some strange issues with my system in regards to high temps, seemingly caused by the CPU simply not respecting the vcore which I set in the BIOS.

 

My motherboard is THIS one, although I believe all gigabyte aorus z390 boards will have a functionally identical BIOS. All the following data is observed from HWMonintor. My CPU Cooler is the 280mm CLC AIO from EVGA. My case is an Enthoo Evolv ITX with 5 140mm noctua fans, so airflow isn't a problem. Also, I've tried setting different power profiles in windows before anyone suggests this. Power supply is also a 650w 80+Gold PSU from EVGA.

 

Running the latest BIOS, and all default settings(everything set to auto, except multicore enhancement disabled), my CPU runs at max 2 core boost (4.8GHz) idling at the desktop, and voltage fluctuates around 1.35 with wild fluctuations ranging from 1.1 volts to 1.4 volts.

 

Then, if I manually set vcore to 1.28 and disable adaptive voltage switching, the voltage at the desktop will fluctuate between 1.1 and 1.35 volts averaging around 1.15.

 

Now, if I run a program like the latest version of prime95(the avx intensive one), then my voltage will initially start around 1.28 where I want it, but it will gradually creep upwards until it reaches around 1.33-1.5V over a timespan of approximately 2-5 minutes.

 

Tweaking Loadline calibration doesn't have an effect on this upward creeping of voltages, in fact it causes it to end up at a higher average voltage.

 

All of this suggests that something is telling the CPU to overvolt, like a fixed overvoltage offset, and something is telling it to turbo. However, all settings that I can think of in the BIOS I've tried manually setting to off or their minimum respective value.

 

Does anyone have any insight to the situation?

[Osmium]

Another thing to note, is I don't believe the VRM is defective. As it seems to be able to deliver consistent voltage while under load. 10 minutes into prime95 or OCCT the voltages are stable at 1.33ish within plus or minus .05 volts. Its just that the voltages are always consistently higher than expected.

[lawngnomeman]

Did you ever find a solution? I'm having a similar issue on my PC

[Osmium]

On 12/31/2018 at 11:38 AM, lawngnomeman said:

Did you ever find a solution? I'm having a similar issue on my PC

 

Sorry for the late reply, didn't get help for this after a few days so I didn't bother checking back.

 

I did find the problem, basically HWMonitor was displaying bogus data.

 

Apparently, the software devs of these hardware monitoring programs have to add profiles for every motherboard, to properly calculate voltage data from the built in sensors on the motherboard. So if you are reading crazy data, you should "shop around" for different voltage monitoring programs.

 

I ended up buying a multimeter and measuring the voltage on the back of the socket, and I found CPU-Z was giving me accurate data.