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Are the 12v+ and the 12v- voltages too low?

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3 replies to this topic

#1 Jackie Coogan

Jackie Coogan

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Posted 09 November 2014 - 08:00 PM

Recently there´s been a strange noise coming from my computer, it sounds like a tick and it varias in it´s volumen, the noise happens so fast and so radomly that I haven´t been able to pinpoint where it comes from but it could be the psu. So I decided to investigate if anything was wrong with the psu by checking out HWmoniter, when I checked it out HWmoniter told me the voltage for the 12v+ and the 12v- where both more or less 4.03. Witch I think is low considering it should be around 12. I Is this a good way to monitor the 12v+ and 12v- voltages? Could the low voltages be related to the wierd noise I´m hearing?  Should I change my PSU?

Edited by Jackie Coogan, 09 November 2014 - 10:29 PM.

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#2 ElfBane


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Posted 10 November 2014 - 04:31 AM

Yes, those voltages are too low. But before changing the PSU check with this utility also ... http://www.bleepingcomputer.com/download/speedfan/ .

#3 jonuk76


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Posted 10 November 2014 - 05:58 AM

You wouldn't have a running computer with those voltages. The 12v rails powers the CPU on modern computers, and the tolerable spec is at most +/- 5% on +12v.  The readings are most certainly not accurate.  It's probable the software is not able to read the computers hardware monitoring chip correctly. Check your hardware monitoring screen in the BIOS, or if you know how check them directly with a multimeter.


"Tick" noises could be anything mechanical like a fan bearing failing or fan hitting it's housing, or a HDD.  As noises resonate through the case they can be difficult to locate.  Noisy fans can be checked for by pressing down on the middle of them gently (while running) with something like a pencil eraser to slow them down.  If the noise stops, you might have found the problem fan.  Intermittent noises are difficult though..


#4 mjd420nova


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Posted 10 November 2014 - 10:17 AM

Somewhere you got the connections wrong on the multimeter and those voltages are not proper, but the unit wouldn't run if they were the real readings.  The ticking could be from a seemingly random area or during a specific function (ie. accessing they hard drive while a particular display is up).  The sound could be the motion of the heads on the hard drive moving to a location on the platter that creates a small tick from the head solenoid as it moves.  Fans are a suspect but would most likely be a steady noise, not intermittent.

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