Is 3.4V output on 3.3V rail safe?

Dadrian Daedalus

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May 25, 2015
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I have a pc with the following config:

core i5 3450,asus p8b75-v motherboard,12gb ddr3 ram,gtx 960,1+2tb hdds,seasonic s12ii 620w psu(the newer model).

Earlier i had a power corsair vx 450 psu but i replaced it with the seasonic unit last year in january.

Recently while monitoring the output voltages of the psu using aida64 ,i observed that while the readings for all other rails appeared to be normal,the reading for the 3.3v rail was a bit on the higher side-around 3.42v to be precise-it was fluctuating between 3.39 to 3.42 volts and sometimes(quite rarely though)increased to 3.45v for a few seconds.

I'm aware that software readings aren't necessarily accurate,but if my psu is indeed generating 3.4v on the 3.3v rail then is it safe to continue using it any further?Will an output of 3.4v potentially damage any components of my pc?

The psu was only purchased last year and has about 4 years warranty remaining-is there any cause for alarm due this issue and do i need to have the psu rma'd?

Is the somewhat high output on the 3.3v rail a common characteristic of this particular psu?Acc. to this review that i found elsewhere,during real world load tests the idle voltage of the s12ii 620 stayed at 3.44V,which increased to 3.45V under load conditions:

https://ru.gecid.com/power/seasonic_...20gb_2015/?s=1

Does the s12ii 620 have any design flaw that could be the cause of this?
 

Vic 40

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It's maybe abit high,but still well within specs. If it stays this way is there no need to worry.
http://en.wikipedia.org/wiki/ATX

Supply (V) Tolerance Range, min. to max. (V) Ripple, p. to p., max. (mV)
+5 ±5% (±0.25 V) +4.75 V to +5.25 50
−5 ±10% (±0.50 V) −4.50 V to −5.50 50
+12 ±5% (±0.60 V) +11.40 V to +12.60 120
−12 ±10% (±1.20 V) −10.80 V to −13.20 120
+3.3 ±5% (±0.165 V) +3.135 V to +3.465 50
+5 standby ±5% (±0.25 V) +4.75 V to +5.25 50
 
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Dadrian Daedalus

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Is the fact that its producing 3.4v on its 3.3v rail enough to warrant sending it for RMA?

Can the continued use of this power supply possibly cause any kind of irreparable damage to my pc?

What problems might arise if the voltage on the 3.3v rail goes out of spec?

Can the voltage on the 3.3v rail be measured from a SATA power connector?If yes,how?
 

Vic 40

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No.



No,like i said it's well within spec.



The pc most likely will restart with mentioning that the pc did shutdown improperly in windows after restart.,can't come up with the right name,but close to this.



no,needs to be done at the 24pin,the molex and sata connectors only have 12V+5V on them.


You don't have to worry,me saying abit high was not the right way to say it,sorry. The readings are well within spec.
 
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