Question Why does HWInfo's +12v sensor reading frequently fluctuate between 11.884-11.980v ?

[The Guy From The Thing]

I've made a post previously about this and I'm more so confused than stressed now. my +12v rail is apparently always sitting at either 11.884 or 11.980v on my Phanteks Revolt Pro 1000w PSU, and in-game (sometimes on idle) it likes to fluctuate a lot between the two of them. here's an example:

https://imgur.com/a/Pvogf4Y

View: https://imgur.com/a/Pvogf4Y



the reading is the same in Bios (+5v is 4.980v and 3.3v is literally 3.32v or whatever); I use an Asus ROG Strix B550-F Motherboard so to my knowledge, even if I used a different PSU without switching the motherboard, these voltages could likely end up being the same.


software isn't really reliable for exact PSU voltage and even if 11.8-11.9v is correct and to be taken at face value, that's well within the ATX spec. but how harmful is it for the voltage to be fluctuating like that? let's assume we can take HWInfo at full, accurate value

as far as I can see, I have no instability, but is it dangerous for the PSU or an indicator of fault if the voltage is so up and down between these 2 values in such short gaps? I've seen someone said Seasonic PSUs have a "micro tolerance" of 0.5%, and taking 0.5% off 11.980 should leave you with around 11.92; mine is going down to 11.884. the difference between 11.980 and 11.884 is 0.096, I believe, which is pretty close to a 0.1v difference; how bad would this be for the PSU if we just assume this is accurate


(don't just say "use multimeter"; currently can't get one, and I'm too lazy to actively test it atm, that's the whole reason I've even looked at the +12v reading on HWInfo)

 

[DSzymborski]

It's unlikely to be a problem, and since it's such an inconsequential issue, you would need to have a proper load tester and oscilloscope to actually explore it in any meaningful way, so there's zero point in worrying about it.

 

[The Guy From The Thing]

It's unlikely to be a problem, and since it's such an inconsequential issue, you would need to have a proper load tester and oscilloscope to actually explore it in any meaningful way, so there's zero point in worrying about it.

could this be considered normal behavior to be experiencing frequent ~0.1v fluctuations? I'm not sure how much ground the "0.5% tolerance" has, I didn't search extensively but my initial search didn't show much. not sure what the significance of this 0.1v fluctuation could be, if it were to indicate a problem, but I like to be better safe than sorry


selfish but I really would love for PSUs to have actual sensors; such a crucial component of the pc, I'd love to have some insight into the current voltages and whatnot but it is what it is

 

[DSzymborski]

could this be considered normal behavior to be experiencing frequent ~0.1v fluctuations? I'm not sure how much ground the "0.5% tolerance" has, I didn't search extensively but my initial search didn't show much. not sure what the significance of this 0.1v fluctuation could be, if it were to indicate a problem, but I like to be better safe than sorry


selfish but I really would love for PSUs to have actual sensors; such a crucial component of the pc, I'd love to have some insight into the current voltages and whatnot but it is what it is

Yes, SeaSonic advertises their top-end PSUs as having that as their tolerance. That doesn't mean that it's the standard in which everything else is dangerous.

It's not a big deal. If it worries you, replace the PSU (there's just about zero chance that this is an RMA thing).

 

[The Guy From The Thing]

Yes, SeaSonic advertises their top-end PSUs as having that as their tolerance. That doesn't mean that it's the standard in which everything else is dangerous.

It's not a big deal. If it worries you, replace the PSU (there's just about zero chance that this is an RMA thing).

what exactly does that tolerance mean, though? the ATX spec is 11.4-12.6, so what is this Seasonic-advertised 0.5% tolerance for exactly?


I won't replace unless it comes out that this is an indicator of defection or something

 

[The Guy From The Thing]

Yes, SeaSonic advertises their top-end PSUs as having that as their tolerance. That doesn't mean that it's the standard in which everything else is dangerous.

It's not a big deal. If it worries you, replace the PSU (there's just about zero chance that this is an RMA thing).

btw when you say “there’s a zero chance that this is an RMA thing”, do you mean that this is not something worth replacing the PSU over or that this is not something they would accept an RMA for


like I said, if this isn’t an indication of defective unit, I won’t replace but I would be surprised if I did try to RMA and it was accepted for this

 

[digitalgriffin]

I've made a post previously about this and I'm more so confused than stressed now. my +12v rail is apparently always sitting at either 11.884 or 11.980v on my Phanteks Revolt Pro 1000w PSU, and in-game (sometimes on idle) it likes to fluctuate a lot between the two of them. here's an example:

https://imgur.com/a/Pvogf4Y

View: https://imgur.com/a/Pvogf4Y



the reading is the same in Bios (+5v is 4.980v and 3.3v is literally 3.32v or whatever); I use an Asus ROG Strix B550-F Motherboard so to my knowledge, even if I used a different PSU without switching the motherboard, these voltages could likely end up being the same.


software isn't really reliable for exact PSU voltage and even if 11.8-11.9v is correct and to be taken at face value, that's well within the ATX spec. but how harmful is it for the voltage to be fluctuating like that? let's assume we can take HWInfo at full, accurate value

as far as I can see, I have no instability, but is it dangerous for the PSU or an indicator of fault if the voltage is so up and down between these 2 values in such short gaps? I've seen someone said Seasonic PSUs have a "micro tolerance" of 0.5%, and taking 0.5% off 11.980 should leave you with around 11.92; mine is going down to 11.884. the difference between 11.980 and 11.884 is 0.096, I believe, which is pretty close to a 0.1v difference; how bad would this be for the PSU if we just assume this is accurate


(don't just say "use multimeter"; currently can't get one, and I'm too lazy to actively test it atm, that's the whole reason I've even looked at the +12v reading on HWInfo)

It's in spec. You are good to go. And those numbers are par for the course with decent quality PSUs.

You have to remember things like wires and connection points can alter things. And near 0 ohm burden resistors variance can change a lot of readings.

 

[The Guy From The Thing]

It's in spec. You are good to go. And those numbers are par for the course with decent quality PSUs.

You have to remember things like wires and connection points can alter things. And near 0 ohm burden resistors variance can change a lot of readings.

the whole frequent ~0.1v fluctuation between 11.884 and 11.980 is all good then? that's a relief, felt weird seeing it so up and down in those quick bursts. it's a lot more streamlined at 11.980 when idle so even if the exact voltages aren't accurate, I feel like the general behavior of the voltages have basis in these readings


thank you. not sure what the 0.5% tolerance from Seasonic is about, but my PSU isn't an exact Seasonic model, so Phanteks might not follow this method and may have changed stuff

 

[Dark Lord of Tech]

It's normal range , nothing to fret about.