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CPU usage high even when idle

Last response: in CPUs
August 1, 2011 12:03:19 AM

Hi all,

I'm having a problem with my CPU running way too fast, even at idle.
The fan's running ridiculously fast and annoyingly loud but I haven't noticed the temperatures increase to any more than they would usually.

Just sitting at the desktop with nothing open, HW Monitor is telling me the fan's running at 6600 RPM.
Opening a webpage and just scrolling up and down will cause the usage to jump quite drastically and the fan to sound like it's about to explode. As I was doing this it would jump up to around 60% CPU usage which I'm pretty certain isn't normal.
I'm reluctant to open anything more demanding now as, as you can imagine, it's worse in games etc.

Before this had started I'd already cleaned out the tower with compressed air as it needed doing and also applied new thermal paste to the heatsink.
I've just reformatted aswell, but for a different reason, so there shouldn't be loads of unnecessary programs running in the background.

Any help would be appreciated.

More about : cpu usage high idle

a c 138 à CPUs
August 1, 2011 2:32:47 AM

there are many software always be some tasks running in the background, in task manager , also scan with antivirus latest update
a b à CPUs
August 1, 2011 12:45:43 PM

check you didnt apply too much thermal paste--too much is not good

check you put the heatsink on properly

check you connected the cpu fan connector properly--making sure the yellow wire is on the pin

software issue wont make the fan run 6600rpm--must be a small fan to run that fast

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August 1, 2011 1:37:06 PM

Thanks for the replies.

It seems to be okay after switching on this morning. I'm guessing it just overheated throughout the day and was struggling to keep cool.

Would it be a problem if the thermal compound spilled over a little bit off the side of the CPU?
I tried to get it off but it was pretty difficult.

If it sounds like something that could cause problems I'll have another go.
a b à CPUs
August 1, 2011 1:50:10 PM

if some spilled off the side you might have put too much on --if its too thick it doesnt work effectively--how much did you use?
August 1, 2011 2:10:42 PM

To be honest, I thought a little much came out. Nothing was coming out so I squeezed a little hard and quite a bit came out.
I didn't think it was too much more than I needed though.

Would you say it's worth re-doing it just to be on the safe side and giving it a good clean?

Also, should you put the compound on both the CPU chip and the heatsink or just the chip?
I've only been putting it on the CPU after getting rid of all the leftover residue.
a b à CPUs
August 1, 2011 2:20:01 PM

if your fan speed has slowed down then it may be fine and temperature is ok on the cpu then you could probably leave it as it is

i usually only do the cpu

have a look on youtube for thermal paste application to see the amount they use
August 1, 2011 2:30:08 PM

Okay, as I've been sitting at the computer for the past hour the fan speed's have been crawling back up and hitting 6.3k rpm.
The only thing that was going on was some internet browsing and installing SC2.

I think I'm gonna reapply the thermal paste and see if that helps.
a b à CPUs
August 1, 2011 2:55:35 PM

i would--must sound like a hoover at that speed
August 1, 2011 3:46:21 PM

If you are using arctic silver, be careful not to get any on any of the components other the the CPU/heat sink. The silver particles in arctic silver are conductive and can short out components.
August 1, 2011 3:49:07 PM

Yeah, it's a pain.

Anyway, I've re-applied the thermal paste, this time using a pea sized blob in the middle and letting the heat sink spread it out and the fan speed upon booting up is down below 3k rpm.
It's gradually increasing again but I guess that's to be expected and it's nowhere near as high as it was before.

I'll keep an eye on it and see how it handles under stress.

I did notice that when I took the heat sink off it came loose with hardly any force required, quite the opposite as to when I last took it off and spent ages wriggling it free.
The thermal paste that I'd put on maybe a fornight ago looked quite blotchy aswell with quite a few gaps in it.

Does it matter that a small amount of compund has reached the underside of the CPU chip?
It's just touching four of the pins. I tried to get it off but I don't think I have anything small enough.
August 1, 2011 3:53:20 PM

jb223 said:

Does it matter that a small amount of compund has reached the underside of the CPU chip?
It's just touching four of the pins. I tried to get it off but I don't think I have anything small enough.

If it were me, I'd try to remove it. On the other hand, if things are working properly you must have used a non-conductive thermal paste which should cause no problems.
August 1, 2011 4:05:43 PM

I'll see how it goes and if I run into any problems I'll try get rid of it.

Fan's back up to 4.7k rpm while just downloading a patch for SC2 and internet browsing. Think that's about normal.

It's also been quite hot here compared to the usual dreary weather so I guess that could be contributing.
August 1, 2011 4:24:33 PM

Fan speed isn't the issue, it's CPU temperature which in turn causes the fan to rotate faster. List your CPU make/model. Ambient temperature can cause slightly higher temps, but they shouldn't be extreme. Do you use an A/C? What are your room temperatures?

You can use HWMonitor to check your CPU core temps.
August 1, 2011 4:32:05 PM

CPU is AMD Phenom II x4 955 ~3.2Ghz.

Don't have air conditioning (guessing that's why A/C is), not sure what the room temperature is.

I've been using HWMonitor to check temperatures and fan speed etc already.

Highest it's been is 52C when I've just entered StarCraft, but I imagine it'll get to about 55-56C whilst I've been in game for a while.
At least that's roughly what it used to get to.
At idle it's around 40C, sometimes a little less and sometimes a little more.

The fan's reaching annoyingly loud speeds again now.

In HWMonitor under 'Fans PWM' I've got three listings: FANPWM0, FANPWM1 and FANPWM2.
Only FANPWM2 is at 99%, is normal for the other two to be at 0%?
August 1, 2011 4:56:12 PM

The max temp is 62°C as seen here.

Preferably you want to keep it much cooler than that. Fans listed as 0 RPM's are either not connected, not working, or the sensors may not be functionng properly. 40°C at idle seems a little high, but is probably due to you having no A/C (yes, air conditioning). Remember, case fans suck in outside air. If you are sucking in hot air it can't cool the CPU as efficiently.

Make sure the fan is connected to the proper fan header on the motherboard. Also, check your bios for smart fan options or the like. Changing this setting may help.
August 1, 2011 5:05:30 PM

I had a quick look in the BIOS the other night but I wasn't really sure what I was doing.

I saw some options for AMD Cool'n'Quiet and some other fan options and I think they were just all set to auto.
I thought that would be best to leave it at.

Just looking into CPU coolers, specifically the Cooler Master Hyper 212+.
Do you think that would help out much, even if it's just that the fan's quieter and not necessarily running slower?
a b à CPUs
August 1, 2011 5:21:23 PM

the fan would run much slower--bigger fans usually are under 2000rpm--my cpu fan spins at 800rpm and my case fans at 600rpm--would be a lot quieter

which cooler you can use would depend on your case and motherboard as some of them are seriously big--it sounds like you only have about a 60mm fan on there now as its hitting 6600rpm--so you need to make sure a 120mm cooler will fit in--its not just the 120mm fan its the height of some of these coolers and wether they clear your ram as well
August 1, 2011 5:21:30 PM

I went into the BIOS and tried to find anything I could related to the CPU fan.

There's AMD Cool'n'Quiet which can be set to auto or disabled. By default it's set to auto.
There's CPU Smart Fan Control which is set to auto, and there's CPU Smart Fan mode which is set to auto rather than Voltage or PWM.

I've disabled the AMD CnC to see what happens along with the Smart Fan control so that the CPU fan is now constantly running at 100%.

The fan's running now at a constant 6.3k rpm according to HWMonitor but the temperatures don't seem to be any lower.
If anything they seem to be slightly higher.

I've also noticed that I'm now getting 99% from FANPWM0 aswell as FANPWM2.
This is the first time I've seen FANPWM0 at anything other than 0%.

I'll keep messing around and see if I can get anywhere.
August 1, 2011 5:29:41 PM

jb223 said:

Highest it's been is 52C when I've just entered StarCraft, but I imagine it'll get to about 55-56C whilst I've been in game for a while.
At least that's roughly what it used to get to.
At idle it's around 40C, sometimes a little less and sometimes a little more.

Actual current temps would be useful. Also, thermal past takes a few days to set at which point the temp should drop a few degrees. Fan speed is always dictated by CPU temp. Even if you get the hyper 212+, it may or may not help. If you are using the stock heatsink the 212+ may offer better cooling, but ambient temps come into play. If it's 80°F (not celsius) or higher, your cooler won't be able to keep up as well.

As an alternative, you can always get a fan controller and manually control the speed. It can be something as simple as the fan mate 2.
August 1, 2011 5:49:17 PM

I've just downloaded CPU-Z and noticed that my core speed is staying at 3.2Ghz and the multiplier at x16.0.

Before it had always run in some power saving mode and turned the core speed down to 800Mhz and multiplier to x4.0 when it wasn't doing anything stressful.

I went into Windows power settings and it's set to balanced as it used to be, then I went into Catalyst Control center to find the CPU usage page where you can adjust what speed it runs at and I can't find it.
It was always under the Power heading but for some reason it's not there.
I'm pretty certain I'm using the same version as I was before.

Any ideas?
August 1, 2011 5:51:26 PM

Catalyst control center is for your video card, not your CPU. For your CPU to throttle back, you need to enable cool&quiet in the bios and set the windows power configuration to minimal, not balanced.
August 1, 2011 6:01:16 PM

I re-enabled Cool'n'Quiet (though I already had) and that didn't do it.

Then I realised I was running a selective startup and it wasn't loading CCC.
I opened it up and the CPU usage panel was back.
Opened up CPU-Z and it had returned to normal, 800Mhz and x4 multiplier.

This has helped it a little with the temperatures seeming a little lower and the fan not being quite as deafening.
August 1, 2011 7:25:45 PM

Right, so I've now tried swinging the tower out from under the desk and sticking an office fan in front of it.
This instantly dropped the temperature and therefore fan speed to much more reasonable levels.

This makes me want to invest in a decent cooler, however if there is something else causing this overheating then a new cooler wouldn't be fixing the problem, only making it more manageable.

Is there any reason why opening a new tab in my browser or just simply scrolling along a page would increase the stress on the system so much?
August 1, 2011 7:29:16 PM

You didn't state which OS you have, so either run the resource monitor (Win 7) or the task manager and see which program is using up CPU. A browser consumes very little CPU unless perhaps watching a video in your browser.
August 1, 2011 7:40:09 PM

I'm using Windows 7.

I ran resource monitor and opened a few tabs in Firefox and scrolled around and the CPU number went from 2 to 20+ and the little graph of CPU usage on the right hand side was hitting almost 100% at these times.

Is this normal?

Should I maybe try using Chrome or another browser and see if I get the same result?
August 1, 2011 7:45:05 PM

Lots of people use firefox and don't have this problem, including me. You might look into updating your chipset drivers and/or lan driver and see if it makes a difference. Create a restore point first in case you need to roll back the changes.
August 1, 2011 7:47:07 PM

Yeah, I've been using Firefox for years and don't think I've ever had this problem.

Those drivers are up to date as I did them yesterday.

Thanks for the quick repsonse times by the way.
August 1, 2011 7:59:29 PM

Well, I'm at the end of my rope. Sorry I can't be of more help. Hopefully someone else can jump in and help you. If I think of anything else, I'll get back to you.
a b à CPUs
August 1, 2011 8:05:36 PM

try booting in safe mode with networking and use firefox to see if its the same--just to rule out your antivirus or other software running in the background causing the 100% cpu usage--i used kaspersky before and opening certain programs made it shoot up to 100% for no reason
August 1, 2011 8:14:01 PM

I'll try booting in safe mode, but what do you mean by 'with networking'?

And no worries, Hawkeye.
Thanks for your help. :) 

a b à CPUs
August 1, 2011 8:17:42 PM

you have the option of safe mode or safe mode with networking--one lets you use the internet one doesnt
August 1, 2011 10:57:34 PM

Thanks, managed to get it to work but I realised something.

When I was looking at the resource monitor and seeing the CPU hitting 100% when opening new tabs in Firefox, I was looking at the blue bar which is Max Frequency.
CPU usage doesn't hit 100%.

It must be that the CPU is going from it's idle speeds to it's max speed every time I'm using the browser.

Is it necessary for the CPU to be at max when just browsing some websites?
a b à CPUs
August 2, 2011 8:33:49 AM

did the fan still run at full speed in safe mode?
August 2, 2011 2:01:41 PM

It was the same in that it was jumping up everytime I opened up tabs or scrolled through a page.

It's not running at full speed since I re-enabled AMD CnC and set the fan control back to auto.

I've ordered the Cooler Master Hyper 212+ which should be here tomorrow.
Even if it doesn't fix the problem, I should have probably replaced the stock cooler ages ago as the noise can really get annoying.
a b à CPUs
August 3, 2011 4:57:20 PM

I've got the Hyper212+ running with my PII X4 840. It's a great cooler, with either AMD or Intel.

I'm running it in a push-pull arrangement, with an extra push and pull fan within close proximity. Which works great when the room temp is down, but when it's hot, its just moving more hot air. I've played games with it that warm in here, and honestly the only thing keeping me from doing it more is my GTX 260, if temps reach 80 the driver crashes.

My CPU's have never given me issue over the heat, and I also run my fans @ 100% seeing as I have 6 case fans with no controller, the cpu fan(s) are not going to be noticed.
August 3, 2011 8:34:09 PM

I've installed the Hyper 212+ now and it's such an improvement.

I can actually hear myself think while using the computer now. :) 

Temperatures are quite a bit cooler too so I've decided to give overclocking a go for the first time.
I'm at 3.6Ghz on my Phenom II 955 on 1.40V. Highest temps are 58C running Prime95.
Would you say that's acceptable?
a b à CPUs
August 3, 2011 8:40:29 PM

temperature looks ok--dont forget prime 95 stresses the cpu far more than real world use so in actual use your temperature wont go that high anyway

glad to see you got there eventually and your ears can get a break now :D 
August 4, 2011 1:13:45 AM

Yeah, makes for a nice change not to have to yell to talk to someone in the same room.

I was reading up on overclocking the 955 and I heard some people say they could get it to 3.8Ghz just on the stock voltage.
Would you say it's worth trying that out for cooler temps or just be happy with what I've got?

Also, is Northbridge Frequency important in overclocking or should I just be concentrating on the CPU multiplier?

Thanks again for all the help.
Most helpful forum I've probably been on. :)