Low voltage readings with no affect

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timoty

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Need some advice to put me at ease. This morning, I received a warning message after rearraging the cabling in my PC. It turns out that, according to the BIOS as well as several monitoring programs, that I have 1.06V for the 3.3V, 1.75V for the 5V, and 4.22V for the 12 V. I know that this isn't accurate because the system starts fine and passes any test I throw at it from Prime95 to Futurmark. I tried swapping out the PSU and even flashed the bios but I still get the low voltage readings. IT is an ASUS P5N32-E Sli motherboard.

So should I be concerned about this or just ignore it?
 
Solution
Obviously, because the system boots and runs, the PSU isn't that bad. Before you swap PSU's, verify the readings with a DMM.

Measure between the colored wires and either chassis ground or the black wires. Yellow wires should be 12 volts. Red wires: +5 volts, orange wires: +3.3 volts, blue wire : -12 volts, violet wire: 5 volts always on. Tolerances are +/- 5% except for the -12 volts which is +/- 10%.
Obviously, because the system boots and runs, the PSU isn't that bad. Before you swap PSU's, verify the readings with a DMM.

Measure between the colored wires and either chassis ground or the black wires. Yellow wires should be 12 volts. Red wires: +5 volts, orange wires: +3.3 volts, blue wire : -12 volts, violet wire: 5 volts always on. Tolerances are +/- 5% except for the -12 volts which is +/- 10%.
 
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timoty

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I'll give the DMM a try. I already tried swapping out the PSU (as noted in the origninal post) but it made no difference. I believe though, that if those voltages were in fact correct, the computer wouldn't even boot. Especially given that it has a 5770 video card. Without the correct power, the LCD wouldn't even come on (not enough power to the video card).
 

timoty

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So, I take it then, that it is just a faulty monitor on the motherboard? In all the PC's I've owned (to many to count), I have never had that happen before. It can't be very common. I just hope that it isn't systemic, leading to other faults that are more problematic.
 
I have seen many boards with this issue(I have had many to play with).

Sometimes its just the way the sensors are read, I have not seen it in the bios however. It has always been with 3rd party software.

Did you get to check with a meter? I mean there is no way it would run with the 12 volt that low.

For fun, look at speedfan pics in Google. you will see lots with strange numbers.
http://www.google.ca/images?q=speedfan&um=1&hl=en&biw=1353&bih=1030&tbs=isch:1,isz:m&source=lnt&sa=X&ei=v4bPTIamPKKLnAfoltGPBg&ved=0CAgQpwU
 

timoty

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5.09, 12.09, and 3.3 just like the doctor ordered. I can only assume that whatever chips(s) on the motherboard that are designed to monitor voltage are dead or corrupt. I flashed the bios and it made no difference. Problem now is that I have no reliable way to monitor my voltages any longer without using a volmeter.
 
In most cases its the same chip as the rest of the hardware monitoring. Most boards use chips from ITE. Since this is a separate chip, flashing the bios will not fix it.

I do not think it is a deal breaker, but if you are worried, you can contact your MB maker if it under warranty for a replacement of the board it self.
 

timoty

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Replace the board, reactivate Windows (at the very least), down time, complaining kids. Nope. Think I'll take my chances. When / If she goes, its time to upgrade. Thanks for the advice. =)
 
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