Large Voltage fluctuations

nathanrjung

Junior Member
Nov 14, 2007
2
0
0
I've got a Gigabyte P965-DS3 motherboard with a CoolerMaster IGreen 500W power supply

I was getting weird random beeping from the PC speaker, and so I've been monitoring voltages and temperatures with Speedfan 4.33 for a couple days. The weirdest readings indicate that -5V randomly goes from around -5V to -8.8V

On another machine with the same motherboard, using a different PSU, the -5V rail is steady within .05 Volts.

Is this a power supply problem? It's only 8 months old

Is it the motherboard?

Thanks for your time,

Nathan
 

Harvey

Administrator<br>Elite Member
Oct 9, 1999
35,059
73
91
It sounds like the -5 volt regulator in your power supply is failing. Stop using it IMMEDIATELY. If it's still in warranty, RMA it. If not, someone who knows how to service it may be able to repair it if it's worth what they'd charge.
 

nathanrjung

Junior Member
Nov 14, 2007
2
0
0
Thanks Harvey

That's what I was suspecting. The PSU is still under warranty. I'll see what Cooler Master will do.

 

jonnyGURU

Moderator <BR> Power Supplies
Moderator
Oct 30, 1999
11,815
104
106
NO!

Your power supply is FINE.

There is no -5V on your power supply. The reading is a bunch of random B.S. numbers that are getting spit out because it doesn't know any better.
 

MarcVenice

Moderator Emeritus <br>
Apr 2, 2007
5,664
0
0
Hahahaha, this is some legendary shit right here. Okay, exagerating, but just wanted to say that. Don't trust software to monitor your voltages.
 

Quiksilver

Diamond Member
Jul 3, 2005
4,725
0
71
Originally posted by: jonnyGURU
NO!

Your power supply is FINE.

There is no -5V on your power supply. The reading is a bunch of random B.S. numbers that are getting spit out because it doesn't know any better.

Lol. I'm sorry but I just had to laugh at that last part.
 

amdfansftw

Member
Nov 21, 2007
192
0
0
Ok so I am having this same exact issue except mine is going from 2.3 up to near 6 volts on the 5V rail in everest home edition. I have a 7950gt that is artifacting and my cpu temps according to everest are 71C. i don't think it's that hot though. i have been on two different power supplies with the same problem with the artifacting with multiple cards that I have RMA'd back to xfx. different mobo as well. so my question is what is making this happen? and what can i do to fix it?
 

Quiksilver

Diamond Member
Jul 3, 2005
4,725
0
71
Ok so I am having this same exact issue except mine is going from 2.3 up to near 6 volts on the 5V rail in everest home edition.
What is it about the part that software does not read voltages accurately? If you want to test your voltages buy a multimeter.


I have a 7950gt that is artifacting and my cpu temps according to everest are 71C. i don't think it's that hot though.

Well if judging by your username you have an AMD processor; which is a sheer guess sames you didn't list any system specs other than your graphics card. Which leaves a few questions.

a) Everest is reporting wrong temps.
b) Everest is reporting right temps but BIOS isn't detecting this temp so its not shutting down.

i have been on two different power supplies with the same problem with the artifacting with multiple cards that I have RMA'd back to xfx. different mobo as well. so my question is what is making this happen? and what can i do to fix it?

You answered your own question by saying 'its not hot enough'.
Fixing it can be easy, make sure all fan's are working as they should, make sure heatsink is properly mounted with the appropriate amount of thermal paste/grease. If nothing is wrong with this, manually set vCore in BIOS just to see if BIOS is over-volting cpu.

Report back.
 

amdfansftw

Member
Nov 21, 2007
192
0
0
fans are clean.

specs
fx-55 on a gigabyte board 2 gb of ram two raptors and the 7950gt psu is a thermaltake 450W

i am just totally stumped
 

amdfansftw

Member
Nov 21, 2007
192
0
0
yeah i do. um the power rating it's a 450W thermaltake i don't know what the ratings are off the top of my head i will have to post them when i can take a look at the psu im at work.
 

NeoPTLD

Platinum Member
Nov 23, 2001
2,544
2
81
If in doubt, get the pin-out chart for the ATX connector and read the voltage with a meter at the back of the connector. Don't trust motherboard monitors.