Power supply +12v

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Hi, i have noticed that my +12v voltage sits are around 11.921 or sometimes lover, around 11.7 when gaming. The +3.3 is at 3.312 and the +5 is at 5.080v, my question is " is it ok to have the +12v lower then 12v? The system has been stable since mid august 09, gaming and doing full HD video editing never had any issues with shutdown, restarts or any power related issues.

Any info or help would be great, cheers people.
 
Soldato
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Table 15. DC Output Voltage Regulation
Output Range Min Nom Max Unit
+12V1DC1
NOTES:
1. At +12V1DC peak loading, regulation at the +12V1DC and +12V2DC outputs can go to
±10%.
±5% +11.40 +12.00 +12.60 V
+12V2DC2
2. At +12V2DC peak loading, regulation at the +12V1DC and +12V2DC outputs can go to
±10%.
±5% +11.40 +12.00 +12.60 V
+5VDC ±5% +4.75 +5.00 +5.25 V
+3.3VDC3
3. Voltage tolerance is required at main connector and SATA connector (if used).
±5% +3.14 +3.30 +3.47 V
-12VDC ±10% -10.80 -12.00 -13.20 V
+5VSB ±5% +4.75 +5.00 +5.25 V

Difficult to read, but go here: http://www.formfactors.org/developer/specs/PSU_DG_rev_1_1.pdf Page 22

edit: Yes, +/- 5% unless under load
 
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Well thanks a lot to both of you, first post ever ! - I've used a few software and they all give me simular results. in reply to your edit does the "edit: Yes, +/- 5% unless under load " not apply at load then, because when doing CPU intensive tasks it is below 12v, maybe at 11.4v which is within the tollarance level.

Main thing is, can it do any damage long term? and would any issues of shown up allready?

thanks again, Benjamin
 
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If there is a problem with the PSU, then expect problems to show up. If its running fine, then dont worry. Software readings are notoriosly unreliable. Get out the multimeter and check it manually (only if you know how to!) its the only way to be sure (to be sure . . . . )
 
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Multimeter, seen a few guides but nope not used one. Thanks for your help, been working fine for 2 months - just did not want it to blow or go up in smoke in the future, heard a few horrow stories.
 
Soldato
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Within specs, it's 5% above or 5% below of 12v as mentioned earlier.

My two rigs have well low readings (below the spec) when in windows, BUT having tested them with a multimeter they are rock solid within the specs. Now I def don't trust the software readers.
 
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Well thanks a lot to both of you, first post ever ! - I've used a few software and they all give me simular results. in reply to your edit does the "edit: Yes, +/- 5% unless under load " not apply at load then, because when doing CPU intensive tasks it is below 12v, maybe at 11.4v which is within the tollarance level.

Main thing is, can it do any damage long term? and would any issues of shown up allready?

The different software is probably getting the info from the same source and just displaying it in a different skin.

What PSU is it? If it's a good brand it's unlikely to do any damage even if it did go bang! A low 12v rail would probably cause random reboots especially during heavy use.

As said above, it's very unlikely that you have anything to worry about but if you want to be sure get your hands on a multimeter.
 
Soldato
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Here's some screenies from a test I done a while back:

12vo.jpg






This was on my Xigmatek 650w psu.

My Corsair 450w shows 6v or something, but is around 11.98v on the multimeter.


AS far as testing on multimeter goes, it's dead simple. I'll have a look for the guide I used.
 
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Its a old antec 600w, not sure on model number. I looked at above screenshot of cpuid and downloaded it for myself, got some very interesting results. It reports the +12v at 4.74, i presume my pc would not boot if this was the case???

cpuidresultsdarkcooleoi.jpg


Multimeter may be the way to go i think, it's weird cause this pc has never missed a beat and has always been 100% stable, (only 2 months since i built it though).
 
Soldato
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It reports the +12v at 4.74, i presume my pc would not boot if this was the case???
You can bet your moneys on that...
While theoretically motherboard's power circuitry for CPU might be able to work HDDs might have slight problems because they need 12V for spinning platter assembly.
 
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So my power supply is fine then? i'm going to check with a multimeter to make sure though. Guess if something was wrong it would of shown up by now, just like to double check - was slightley worried over long term damage.
 

RJC

RJC

Don
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Software voltage monitors show my 12v line as 3v, checked it with my multi-meter and it reads 12.01v.

iIf your system is running fine you will have nothing to worry about.
 
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