Minor Fluctuations in Fan Speed - PSU?

Gyroscope · 07-24-2008, 12:37 PM

I've noticed lately some minor fluctuations in the fan speeds. The faster the speed, the greatest the fluctuations. Running at, say, 2700 RPM, the fluctuation is +- 150RPM; less at ~1600

I suspected a voltage issue, but trying to check with several programs (e.g. Speedfan, PC wizard), the readings are incredibly unreliable. Speedfan gives for +12V anything between...3V and 10.95, while PC wizard usually doesn't even report a voltage. Only once did it give me a...+15.50V

I suspect a PSU problem, but although it's only 300W, my system is rather low in demands - no hungry graphics cards or anything.

a) Is there any chance it's something else, other than the PSU? I would be ready to believe it's a measuring issue (i.e. the voltage readings are wrong), if it weren't for those pesky fluctuations - albeit small ones
b) Could you suggest (yet) another program that I could use to measure the voltage?

Thanks

**linderman** · 07-24-2008, 01:02 PM

there is NO monitoring program that is really accurate you best bet is to buy a cheap digital multimeter and check your voltages for yourself

at idle and at heavy workload

**linderman** · 07-24-2008, 01:02 PM

Test your power supply with a multi meter

~~OMGmissinglink~~ · 07-24-2008, 01:11 PM

CPU fan fluctuations are most likely fan controller in bios settings, you can disable fan controller.. just make sure your cpu fan is spinning.

Gyroscope · 07-24-2008, 01:22 PM

Thanks for the replies. I kinda suspected that I'll have to check the voltages myself to be sure, but you know how it goes...We always look for the easiest way out, right?

The computer works normally, no big issues, really. Fans kick in when temperature rises, they slow down when temp goes down. I guess I'll have to monitor the situation and try to measure the voltage, like we said,

Thanks

**linderman** · 07-24-2008, 04:01 PM

it normal for cpu and psu fans to raise and lower with temp changes

but I would still check the psu to be sure ..... especially when its working hard

I would be worried about any 300 watt power supply unless you are running an Intel P3 system

~~OMGmissinglink~~ · 07-24-2008, 06:13 PM

voltages does not cause changes in cpu fan speed the bios fan controller does, you can set fan speed "disabled" in bios the fan should run full speed.

Gyroscope · 07-24-2008, 09:40 PM

Quote:

Originally Posted by OMGmissinglink

voltages does not cause changes in cpu fan speed the bios fan controller does, you can set fan speed "disabled" in bios the fan should run full speed.

My BIOS (Phoenix 3.48) doesn't control the fan (ie there's no fan speed option). But even so, why would someone want the fan to run full speed?? That would be terribly noisy!

~~OMGmissinglink~~ · 07-24-2008, 10:08 PM

I'd like mine to be noisy then I know its running .. i'm positive there is an option in bios that controls cpu fan.

~~OMGmissinglink~~ · 07-24-2008, 10:25 PM

This is your bios options, you can change the parimeters in windows advanced power options

Suspend Mode:

The options are S1, a suspend state where the computer is running in a low-power mode, and S3, a standby state where the power is reduced or turned off for most components, however, system memory remains active.

Gyroscope · 07-24-2008, 10:57 PM

Nop, sorry. The only power options available are "after AC power failure" and "WOL in S4"...

**linderman** · 07-25-2008, 04:39 AM

noisey = cool .......... quiet = hot

hot kills computer parts / END of story

Gyroscope · 07-25-2008, 05:11 AM

Quote:

Originally Posted by linderman

noisey = cool .......... quiet = hot
hot kills computer parts / END of story

Quite true :)

I've been rethinking the whole thing today, and I think I'm gradually becoming paranoid over computer things. The more I search, the more "problems" I discover. I think I'll take a break from this...sport :)

FWIW, here's a screenshot with the fan speed fluctuation. Not much, -+ 100 maybe @ 4000RPM. The increase 2/3rds of the way was a manual increase from 85% to 90% or something like that

07-24-2008, 12:37 PM	#1 (permalink)
Gyroscope Registered User Join Date: Jul 2008 Posts: 12 OS: Windows XP SP2	Minor Fluctuations in Fan Speed - PSU? I've noticed lately some minor fluctuations in the fan speeds. The faster the speed, the greatest the fluctuations. Running at, say, 2700 RPM, the fluctuation is +- 150RPM; less at ~1600 I suspected a voltage issue, but trying to check with several programs (e.g. Speedfan, PC wizard), the readings are incredibly unreliable. Speedfan gives for +12V anything between...3V and 10.95, while PC wizard usually doesn't even report a voltage. Only once did it give me a...+15.50V I suspect a PSU problem, but although it's only 300W, my system is rather low in demands - no hungry graphics cards or anything. a) Is there any chance it's something else, other than the PSU? I would be ready to believe it's a measuring issue (i.e. the voltage readings are wrong), if it weren't for those pesky fluctuations - albeit small ones b) Could you suggest (yet) another program that I could use to measure the voltage? Thanks __________________ -- Windows XP SP2, Desktop PC (HP), USB mouse, PS2 keyboard, 512 RAM, MSI-AMETHYST-M, AMD Athlon 64 3500+

07-24-2008, 01:02 PM	#2 (permalink)
linderman Moderator, Hardware Team Join Date: May 2005 Posts: 13,666 OS: win 2000 pro / Win XP pro My System	Re: Minor Fluctuations in Fan Speed - PSU? there is NO monitoring program that is really accurate you best bet is to buy a cheap digital multimeter and check your voltages for yourself at idle and at heavy workload __________________ If you cant be polite and friendly; then please be silent.

07-24-2008, 01:02 PM	#3 (permalink)
linderman Moderator, Hardware Team Join Date: May 2005 Posts: 13,666 OS: win 2000 pro / Win XP pro My System	Re: Minor Fluctuations in Fan Speed - PSU? Test your power supply with a multi meter __________________ If you cant be polite and friendly; then please be silent.

07-24-2008, 01:11 PM	#4 (permalink)
~~OMGmissinglink~~ Troubled Join Date: Sep 2006 Posts: 1,535 OS: XP Pro sp2 My System	Re: Minor Fluctuations in Fan Speed - PSU? CPU fan fluctuations are most likely fan controller in bios settings, you can disable fan controller.. just make sure your cpu fan is spinning.

07-24-2008, 01:22 PM	#5 (permalink)
Gyroscope Registered User Join Date: Jul 2008 Posts: 12 OS: Windows XP SP2	Re: Minor Fluctuations in Fan Speed - PSU? Thanks for the replies. I kinda suspected that I'll have to check the voltages myself to be sure, but you know how it goes...We always look for the easiest way out, right? The computer works normally, no big issues, really. Fans kick in when temperature rises, they slow down when temp goes down. I guess I'll have to monitor the situation and try to measure the voltage, like we said, Thanks __________________ -- Windows XP SP2, Desktop PC (HP), USB mouse, PS2 keyboard, 512 RAM, MSI-AMETHYST-M, AMD Athlon 64 3500+

07-24-2008, 04:01 PM	#6 (permalink)
linderman Moderator, Hardware Team Join Date: May 2005 Posts: 13,666 OS: win 2000 pro / Win XP pro My System	Re: Minor Fluctuations in Fan Speed - PSU? it normal for cpu and psu fans to raise and lower with temp changes but I would still check the psu to be sure ..... especially when its working hard I would be worried about any 300 watt power supply unless you are running an Intel P3 system __________________ If you cant be polite and friendly; then please be silent.

07-24-2008, 06:13 PM	#7 (permalink)
~~OMGmissinglink~~ Troubled Join Date: Sep 2006 Posts: 1,535 OS: XP Pro sp2 My System	Re: Minor Fluctuations in Fan Speed - PSU? voltages does not cause changes in cpu fan speed the bios fan controller does, you can set fan speed "disabled" in bios the fan should run full speed. Last edited by OMGmissinglink : 07-24-2008 at 06:14 PM.

07-24-2008, 10:08 PM	#9 (permalink)
~~OMGmissinglink~~ Troubled Join Date: Sep 2006 Posts: 1,535 OS: XP Pro sp2 My System	Re: Minor Fluctuations in Fan Speed - PSU? I'd like mine to be noisy then I know its running .. i'm positive there is an option in bios that controls cpu fan.

07-24-2008, 10:25 PM	#10 (permalink)
~~OMGmissinglink~~ Troubled Join Date: Sep 2006 Posts: 1,535 OS: XP Pro sp2 My System	Re: Minor Fluctuations in Fan Speed - PSU? This is your bios options, you can change the parimeters in windows advanced power options Suspend Mode: The options are S1, a suspend state where the computer is running in a low-power mode, and S3, a standby state where the power is reduced or turned off for most components, however, system memory remains active.

07-24-2008, 10:57 PM	#11 (permalink)
Gyroscope Registered User Join Date: Jul 2008 Posts: 12 OS: Windows XP SP2	Re: Minor Fluctuations in Fan Speed - PSU? Nop, sorry. The only power options available are "after AC power failure" and "WOL in S4"... __________________ -- Windows XP SP2, Desktop PC (HP), USB mouse, PS2 keyboard, 512 RAM, MSI-AMETHYST-M, AMD Athlon 64 3500+

07-25-2008, 04:39 AM	#12 (permalink)
linderman Moderator, Hardware Team Join Date: May 2005 Posts: 13,666 OS: win 2000 pro / Win XP pro My System	Re: Minor Fluctuations in Fan Speed - PSU? noisey = cool .......... quiet = hot hot kills computer parts / END of story __________________ If you cant be polite and friendly; then please be silent.