OT - Early Warning System

TomG wrote on 2/10/2010, 5:34 AM

My main system is making sounds and I don't like it. It sounds like a fan constantly changing speeds. I have four fans in my system:
1. Exhaust fan attached to case
2. Power source fan
3. Video card fan
4. CPU fan

It doesn't feel like there is any heat building up within the case and upon visual inspection, the case fan and power supply fan don't appear to be changing speed. Do you think this is an early warning of pending system failure? Has anyone had this happen to them and what did you do?

Thanks,
TomG

Comments

farss wrote on 2/10/2010, 5:53 AM

Open PC, check for buildup of dust especially in CPU heatsink.

The tiny PC I'm typing this on winds the CPU fan speed up briefly pretty regularly when the load increases, done this since I built it and it's quite normal. If your PC has just started doing this it's likely dust clogging a heatsink and yes if you don't attend to it soon it could lead to real problems. Don't panic, the CPU will probably start to go wonky before it really fries but a good dust off/out should be considered sooner rather than later

Bob.

craftech wrote on 2/10/2010, 5:53 AM

Are both the CPU fan AND the video card fan changing speed along with the PSU fan?

Can you tell? Use a stethoscope (real or toy or homemade),

If all three do it at the same time, the most likely culprit is the PSU.

John

amendegw wrote on 2/10/2010, 5:54 AM

Speedfan: http://download.cnet.com/SpeedFan/3000-2094_4-10540297.html

However, before I got too involved in temperature monitoring, I'd open up the case and blow out the dust bunnies.

Good Luck,
...Jerry

richard-amirault wrote on 2/10/2010, 10:13 AM

Use a stethoscope (real or toy or homemade)

I often did this at my day job to find the source of a problem sound. A short piece of hollow hose worked just fine .. but then we had a lot of the stuff hanging around.

You don't need to use both ears for this. You just need to get at least one ear "closer" to the sound so you can tell exactly where it is coming from.

gpsmikey wrote on 2/10/2010, 10:19 AM

In my experience, the most common failure along those lines is the cheap little fan on the video card. I have had a number of them fail (typically they have bushings instead of ball bearings and tend to make very strange noises when the bushings get loose). I would definitely start with dust bunny removal though (I buy the cans of "dust-off" in the 4-pack at Costco ). Keep the cans upright when using to avoid spraying the liquid into the area though.

mikey

TomG wrote on 2/11/2010, 5:38 AM

Thanks for your suggestions!

Yes, I did open it up and cleaned it up. I think that helped the main problem although I am still getting random times of fan acceleration (lasts around 3-4 minutes) maybe 1-2 times a day. Computer runs all day. I built the system in '07 (a real dinosaur) but it has run great with no problems (until now). I don't feel any heat coming out of the exhaust (except for the power supply), but I do smell the heat on occasion. On inspection, the CPU fan looks like it is running fine but not as sure about the video card fan.

I'll watch it and it might be time to upgrade to a new video card (or maybe rebuild my computer (ugh)).

TomG

craftech wrote on 2/11/2010, 9:30 AM

The quickest way to reduce heat buildup is to take the cover off the computer and run it that way. It will also be easier to tell if all fans are changing speed as I described above. If that is the case you will probably only need to replace the PSU as I said above. It's probably not regulating the voltages properly, thus the changes in fan speeds. While there is (are) voltage regulator (s) on the motherboard, if those are faulty it would most likely cause operational problems (lockups, etc). Fan speed is directly related to voltage applied from the PSU connector. In fact a common fan mod is to change the voltage to the fan by switching around some of the wires on the connectors to say run it at 7.5 or even 5 volts in order to run it slower. If it is happening all by itself, the voltage from the PSU is probably NOT constant. But it would most likely affect all fans.

John

farss wrote on 2/11/2010, 12:39 PM

Take the fan off the CPU heatsink to get the heatsink really clean. I've found it very hard to get the fins really clean with the fan in the way. Them dust bunnies play hide and seek.

Bob.

amendegw wrote on 2/11/2010, 1:26 PM

"Take the fan off the CPU heatsink to get the heatsink really clean. I've found it very hard to get the fins really clean with the fan in the way."If you remove the entire heatsink from the CPU, I would suggest that you have some CPU Thermal paste handy. You can get it here: http://www.newegg.com/Store/SubCategory.aspx?SubCategory=85&name=Thermal-Compound-Grease I think I've found it at Radio Shack as well.

Also, I like to use rubbing alcohol to make sure the top of the CPU and the bottom of the heatsink are cleaned of all the old paste before applying new..

Good luck!
...Jerry