[mattliston]

I have tried a variety of settings in my sig rig in the DIGI+ power menu inside the BIOS, and I have still failed to smooth out all the voltages.

For those with signatures hidden, system specs are following:

year 2017 FX 8320E

G.Skill TridentX 2400, 2x8gb 10-12-12-31-43-2T

Crosshair 5 Formula Z

EVGA Supernova G2 850watt

rest un needed concerning todays thread.

EDIT using HWinFO64 5.96

CPU/NB graph seriously spikes between 1.349 and 1.396. at random intervals, if I hit the fit Y button again, I have seen as low as 1.33 something and 1.4 something,, apparently catching very rare huge spikes and dips

Vcore graph is very nice, flat and with a few very minor dips and peaks with a tiny difference. Love it.

VIN0 graph is spiking between 1.488 and 1.515, excessive activity, but a little less than the cpu-nb is

voltage ranges were seen by hitting the fit-Y button on HWinfo64

currently, sitting at DIGI+ settings of 140% cpu current, fast power response on cpu and nb, HIGH llc cpu, HIGH llc on northbridge. VRM settings are at extreme for current balancing, and frequencies of power delivery are in middle range. 420 on cpu, and 350k for ram

changing settings appears to do nothing to aleviate this issue.

going back to full factory clocks and voltages, the cpu runs 3.2 GHZ at 1.175 volts quite happily and al;most removes all spikes related to CPU.

northbridge, even at a clock of 2400mhz and the necessary 1.20 volts to keep it happy, still has lots of spiking but range is closed to around a 0.1 difference.

Apologies for no screen shots, I dont have any online hosting

My biggest question regarding this, is this a sign of this motherboard beginning to fail? I did not see this level of spiking with any previous cpus, though I muist admit, I did not pay attention to voltage and temperature conditions nearly as much as I am now with this new-to-me 8320e which actually can run a 2800MHz northbridge during testing. and thats with a minor ram overlcok towards 2500MHz and a command rate of 1!

 

[farmdve]

Don't trust software very much, I also had varying voltages, measured PSU with multimeter and found out everything was fine. However to truly measure noise you need something like an oscilloscope, preferably digital to store the samples.

 

[miklkit]

My Sabertooth does not have any spikes in the cpu/nb with 2 different cpus used. I do not know what VIN0 is. The closest thing I have to it is dram voltage which I run in the 1.6-1.65v range and the vcore. I also never ran the cpu/nb over 1.3 volts.

The only time I remember seeing voltage fluctuations was when I was using a Thermaltake psu that was infamous for "dirty" power.

 

[mattliston]

Revisiting this because while doing quite a few recent sessions of northbridge and HT-Link overclocking, I discovered I had left my VDDA voltage quite low testing how low I could get temps while only 4GHz .

changing the VDDA from 2.21 back to default 2.5 SIGNIFICANTLY smoothed voltage spiking. Perhaps my VDDA votlage is not showing correctly in BIOS/software when it is set fairly low, and maybe it was actually much lower than 2.21 . 2.5 however, shows near perfect.

The reason I originally created this thread was because the voltage spiking was sort of following package temp spiking and temperatures during big spikes. stability was also a bit questionable.
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Bottom line, keep the VDDA at or a little above 2.5 when doing more than say, 4ghz on FX.