Question +12v Rail Experiencing 0.1v Fluctuations? Is This Bad or Am I Stressing Myself Out?

May 1, 2023
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hello, I have a Phanteks Revolt Pro 1000W PSU, and to my understanding that is a Seasonic PSU, which is why I got it around 2-3 months ago. I use HWInfo64 to monitor everything, and I have also checked the Bios, both of which have the exact same +12v rail voltages

the +12v fluctuates between 2 values: 11.884v and 11.980v, which is a ~0.1v fluctuation (0.096 to be exact). this is within the spec range as I am aware but it fluctuates pretty frequently on idle, and sometimes in games as well (ik software isn't 100% reliable here so it's very hit or miss):

View: https://imgur.com/a/4ocDrRK


this should be a sample of me while 'idle', watching yt and browsing Chrome and such. is this a sign of faultiness/something bad, or am I stressing out over something minor here?


if necessary, my 3.3v is usually between 3.31 and 3.32, while my 5v rail is always a solid 4.98v
 
According to this you well within spec

thank you for this, I didn't know the spec ranges of the 3.3 or 5v rails; is there any reason at all to be concerned over frequent 0.1v fluctuations in the 12v rail though or can I ignore it
 
its so tiny I wouldn't worry about it.

I have an RM1000x and today its minimum was 11.880 and max was 12.096, average of 12.019v

I think tis normal for it to fluctuate. You unlikely to get one that is always same level.


what CPU do you have?

i generally don't watch my 12v chart in hwinfo but mine seems to sit on 12.024 all the time. It does depend on what PC is doing, Starting a YT video uses some on my side, typing does it as well

ideally you best using a multi meter as software like hwinfo isn't the most accurate.

Seasonic don't make bad PSU, I had one up until January - only replaced it as my GPU needed more power.
 
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its so tiny I wouldn't worry about it.

I have an RM1000x and today its minimum was 11.880 and max was 12.096, average of 12.019v

I think tis normal for it to fluctuate. You unlikely to get one that is always same level.


what CPU do you have?

i generally don't watch my 12v chart in hwinfo but mine seems to sit on 12.024 all the time. It does depend on what PC is doing, Starting a YT video uses some on my side, typing does it as well

ideally you best using a multi meter as software like hwinfo isn't the most accurate.

Seasonic don't make bad PSU, I had one up until January - only replaced it as my GPU needed more power.
I have a Ryzen 7 5800x and an RTX 3070 in my pc. were those fluctuations on your RM1000x from idle, or did you have load on it. my PSU runs the same values (11.88-11.98) even at load, unless I'm full stress testing the GPU

ik HWInfo and even the Bios aren't completely reliable but I feel like they could still serve as indicators if something is wrong. just wanted to check
 
mine were at idle. I haven't done anything stressing on PC all day apart from watch videos. I just restarted PC so its all different now.

Ryzen CPU constantly waking and sleeping cores so that could be part of it.

Only charts I watch all the time in HWINFO, on my 3600xt, are Core Temps and Average Effective Clock. I have never really worried about power, especially since my last 2 PSU were Seasonic.

my 3.3v changes more often than my 12v
 
mine were at idle. I haven't done anything stressing on PC all day apart from watch videos. I just restarted PC so its all different now.

Ryzen CPU constantly waking and sleeping cores so that could be part of it.

Only charts I watch all the time in HWINFO, on my 3600xt, are Core Temps and Average Effective Clock. I have never really worried about power, especially since my last 2 PSU were Seasonic.

my 3.3v changes more often than my 12v
I never thought about the cores constantly waking and switching c-states being a factor in these fluctuations, that makes sense

PSU had me freaked out because it dropped to ~11.78 and dropped the PCIe voltage down to 11.8 as well during a Heaven Benchmark test. in the end, it was because I had no FPS cap on so my GPU was running at 100% but got me all paranoid
 
Mine dropped to 11.880 in heaven - GPU temps didn't even seem to notice I was running it. Odd my FPS increases in it if I move mouse cursor.
My motherboard doesn't seem to show PCIe voltage
Z7NeUyQ.jpg
 
Mine dropped to 11.880 in heaven - GPU temps didn't even seem to notice I was running it. Odd my FPS increases in it if I move mouse cursor.
My motherboard doesn't seem to show PCIe voltage
Z7NeUyQ.jpg
PCIe should be in your GPU section, for me it's under "GPU Rail Voltage" and you expand the subsection to see a list of voltages. PCIe +12v Input Voltage should be the first one

for me, Heaven dropped my PSU and PCIe voltages and spiked my GPU wattage like crazy until I set Vsync on, after that I experienced next to no voltage drops, and lower wattage. so it was definitely an FPS thing

this has been good information to have, thank you for this
 
AMD GPU don't appear to show it, and I don't see it in their drivers performance screen either.
5UBTYDj.jpg

above not taken while running below. hence framerate is 0
GUU5trd.jpg
ah, AMD GPU is probably why it doesn't show. with Vsync on in Heaven, my +12v is the normal 11.8-11.9 readings, PCIe is a fairly solid 12v, and temps are just fine around 50c. fans don't go overdrive either


never actually heard coil whine until I ran HB without Vsync and let the GPU go full throttle lol, since I don't usually have it at all
 
if i remove my limiter, heaven runs at 250 to 360fps, depending on scene. GPU did notice that and was running at 60c. Strange that it sits on minimum fps allowed unless I turn off the restrictions ... that seems odd. Maybe I make both minimum and max the same.

I don't think I got any coil whine. Could be cause I still had Freesync on. Or maybe my card just doesn't do it. I have helped someone else with my exact card model and he was getting it... that was a few days before I installed mine and I was a little concerned. Only thing I ever hear from my PC is fans.
 
if i remove my limiter, heaven runs at 250 to 360fps, depending on scene. GPU did notice that and was running at 60c. Strange that it sits on minimum fps allowed unless I turn off the restrictions ... that seems odd. Maybe I make both minimum and max the same.

I don't think I got any coil whine. Could be cause I still had Freesync on. Or maybe my card just doesn't do it. I have helped someone else with my exact card model and he was getting it... that was a few days before I installed mine and I was a little concerned. Only thing I ever hear from my PC is fans.
my monitor doesn't support Nvidia's version of Freesync (GSync, I'm pretty sure?). for me, Heaven Benchmark ran without an FPS limit from the start, I had to turn it on rather than it being on by default

usually I don't get any coil whine from the GPU or PSU as far as I know unless it's a full load like HB puts out without any Vsync.

or maybe I do get whine from the PSU, but I haven't been able to tell; got headphones on, my ceiling fan, and my PSU is mounted on the bottom, under my desk, near the wall. under normal gaming load, it does make a degree of sound that I can hear if I go underneath the desk and listen for it, which I assume is the fan