Need help interpreting values

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justlnluck
Posts: 74
Joined: Sun Mar 21, 2004 12:12 am
Location: California

Need help interpreting values

Post by justlnluck » Mon Nov 08, 2004 12:20 pm

I installed Speedfan yesterday to take a look at my temperatures and I am a little concerned with the results shown below. The temps seem rather low. I don't have any case fans...only have the cpu fan and the psu fan. But the computer does feel cold to the touch even though it is on 24/7. I am a newbie when it comes to voltages, so I don't know if these are good values or not. I also notice the voltages (rails?) are fluctuating. Is this a bad sign?

CPU fan: 3309 rpm
PSU fan: 767 rpm

CPU temp: 29C
MB temp: 25C
HDD temp: 28C

Vcore1: 1.50V
Vcore2: 2.54V
+3.3 V: 2.94V
+5V : 3.20V
+12V : 7.36V

-12V : -6.11V
-5V : -5.91V
+5V : 2.04V

Vbat : 0.00V :?

the_smell
Patron of SPCR
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Joined: Fri Aug 29, 2003 10:58 am
Location: Sheffield, UK

Post by the_smell » Mon Nov 08, 2004 12:47 pm

If your system is running stable I wouldn't worry about having low temperatures or strange voltage values! Are the temperatures measued at idle? What heatsink are you using? Do you have cool n' quiet in operation?

To get correct voltage values try looking the the BIOS and then maybe it might be worth trying motherboard monitor instead of speedfan.
It might be worth calibrating your cput temperatures to make sure they are being reported correctly:
http://www.silentpcreview.com/article191-page1.html
Then maybe try running something that should stresses the cpu a bit like cpu burn (or if you don't normally run folding at home :) ) and look at the temperature rise.

justlnluck
Posts: 74
Joined: Sun Mar 21, 2004 12:12 am
Location: California

Post by justlnluck » Wed Nov 10, 2004 7:35 pm

Thanks for the info Smell

Yeah, my system appears to be stable but I want to make sure my power supply is ok. In the BIOS menu under PC Health Status it lists the following:

VCC Core Voltage: 1.47V
VCC 2.5V: 2.54V

The VCC Core occasionally wavers from 1.47 to 1.45 or 1.48 and the VCC 2.5V wavers from 2.54V to 2.56V. Is it normal to see some wavering? And are these values what most people have? Thanks so much!!

silvervarg
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Location: Sweden, Linkoping

Post by silvervarg » Thu Nov 11, 2004 12:58 am

Small fluctuations in voltage are acceptable (but not really good).
What does worry me a little bit is that some of the values you posted are way out of spec.
+5V : 3.20V
+12V : 7.36V

-12V : -6.11V
-5V : -5.91V
If these values would really be true nothing would work. The machine would not post, harddrives would not spin up etc.
So I guess the readings are really off. Start by checking what all the readings in bios says or even better measure the voltages with a multimeter (at least the +5V and +12 are easy to measure).
You might not want to bother with the -5V since that is typically not used anymore.

kesv
Posts: 300
Joined: Fri Nov 07, 2003 8:44 am

Post by kesv » Thu Nov 11, 2004 3:37 am

justlnluck wrote: In the BIOS menu under PC Health Status it lists the following:

VCC Core Voltage: 1.47V
VCC 2.5V: 2.54V

The VCC Core occasionally wavers from 1.47 to 1.45 or 1.48 and the VCC 2.5V wavers from 2.54V to 2.56V. Is it normal to see some wavering? And are these values what most people have? Thanks so much!!
Those voltage wavers are within +/- 2% so it's nothing to worry about. Actually I think the voltage measuring ability of those MB monitor chips is probably no better than that. Meaning what you might be seeing is really the error marigin of the chip and not true voltage fluctuation.

What silverarg mentioned is the really important part. You need to check the +5V and +12V rails. Those are the ones that power most of your pc's components and the figures you have from speedfan are way off. The 12V rail looks to be ~39% off target, which would really mean your machine shouldn't even boot if true.

justlnluck
Posts: 74
Joined: Sun Mar 21, 2004 12:12 am
Location: California

Post by justlnluck » Thu Nov 11, 2004 10:28 am

Thank you both for the additional insight. I just used SiSoftware Sandra to see what voltages it detected and these values look even worse!

CPU Voltage: 1.50V
Aux Voltage: 2.54V
+3.3V Voltage: 2.94V
+5V Voltage: 3.04V
+12V Voltage: 5.87V
-12V Voltage: -6.03V
-5V Voltage: -5.91V
Standby Voltage: 1.59V

I'm not sure if there's a place in my BIOS that shows additional voltages. I don't own a multimeter, but maybe I should make an investment in one just for peace of mind?

justlnluck
Posts: 74
Joined: Sun Mar 21, 2004 12:12 am
Location: California

Post by justlnluck » Thu Nov 11, 2004 10:40 am

Update: I am sitting here watching the Speedfan values change in realtime and the voltages are going all over the place. For example here's the range of my +5V and +12V

+5V: 3.06, 3.08, 5.13, 5.27

+12V: 6.04, 8.70, 10.14, 10.69, 12.41, 12.48

Everytime I look at the screen, I see a new value!

burcakb
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Location: Turkey

Post by burcakb » Thu Nov 11, 2004 1:21 pm

Speedfan and Sandra readings are not necessarily true. They take measurements at addresses common to most motherboards and might not necessarily match your case.

I'd suggest installing Motherboard Monitor. It won't control your fans but it's got direct support for your motherboard, so you should get more reliable readings.

As for your CPU temps, if you're using a good HSF with a 3300 rpm fan and reporting idle temps, yeah, those numbers would be reasonable. 3300rpm is way too high (because it would be noisy) for most of us here :)

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