Sign in with
Sign up | Sign in
Your question
Closed

Dual core: 1 core locking up at 100%, no process?

Last response: in CPUs
Share
October 20, 2008 8:03:06 AM

Am puzzled: Have a new system with an Intel dual core (E2180), 2G memory, running XP Pro (all MS updates installed).
All is working fine, then for no apparent reason, 1 core goes into 100% load (task manager on screen). The only way to recover is to reboot (hard reset) the machine. After a while (an hour - few minutes), it happens again. quite annoying...
Anyone any suggestions for a) the cause and b) the solution?
Thanks, Onno
October 20, 2008 11:21:50 AM

If you look in the task manager processes tab and sort by CPU usage (click on the CPU column heading to toggle sort by most / least CPU usage), which process is hogging all the CPU when this happens (System Idle Process doesn't count)?
October 20, 2008 2:25:51 PM

That's the strange part: there is no process (other than idle) over a few percent, all together floating between 5-10%. Still, in the task manager, performance tab, 1 core (left window) shows a 100% load. The right window shows a squigly line in the low percentages. It's always the left one which goes to 100%, never the right one.
Related resources
a b à CPUs
October 20, 2008 2:52:22 PM

have you ticked the 'show processes from all users' -box in the task manager window?
October 21, 2008 7:56:52 AM

Dear Kari, yes, box ticked.
November 18, 2008 4:42:50 PM

I am having the exact same problem. I was running Internet Radio via Windows Media Player and then all of a sudden my sound started crackling/halting. Mouse movement was then VERY jagged and it seemed like I was only getting about 20% performance than usual.

I checked Windows Task Manager and I found the same thing as the original poster - one core is nearly 100% and the other is basically sitting idle. No processes eating up any CPU either according to Task Manager.

My specs are:

Dell Inspiron 6400
Intel Core 2 T7200 2GHz
2GB RAM
Windows XP Pro

I have been running XP Pro for about 9 months now (it originally came with Vista Ultimate).

And just as I am typing this message the 100% usage core has now dropped back down to almost idle and XP is running at normal speed again. The only thing I did was go to msconfig (Start->Run->"msconfig" [ENTER]) and selected the Diagnostic Startup option (but have not yet restarted).

I'll restart now and see what happens...


EDIT: changed "minimal startup" to the proper term of "Diagnostic Startup"
November 18, 2008 5:15:43 PM

The same thing started happening again, and in fact I think it started whilst I was shutting down (before the restart) because that Windows shutdown sound was crackling.

In Diagnostic Startup (via msconifg) the first core was at 100% again whilst the other idle.

I have now restored to the Normal Startup and encountered the same 100% CPU problem for about the first 3-5 minutes, and after that the CPU has returned to normal (which is near idle). Very strange. I will reboot with some sort of Linux Live CD and see if the same thing happens.
November 19, 2008 4:14:27 PM

Using a Ubuntu Live CD, this problem is not occurring.

So I have concluded that it's most likely an XP problem.

Furthermore, I have performed zero hardware changes but yet have now started receiving the "windows hardware has changed significantly since first activation. 3 days left to re activate" message.

Does anyone have any ideas or suggestions?
November 19, 2008 7:27:59 PM

My notebook came with an OEM Vista Ultimate but I have since put a clean (and legal) install of Windows XP Pro on it (I had to manually download and install all the drivers).

I am currently still in Ubuntu Live CD mode and in the process of running Spybot S&D and Ad-Aware (using Wine for Linux) over the entire hard drive to see if they catch any spyware/adware/malware. Fingers crossed.
November 19, 2008 9:09:45 PM

Keep in mind that a process at 50% is using all of one core (on a dual core). So you might be looking for a 100, but there won't be one, look for the 50. Also, make sure you are view processes from all users.

Hope that helps.
November 19, 2008 9:29:44 PM

I did check processes from all users and no process was over 10%, let alone 50%.

I've still got Spybot churning away in the background, although I think it may have gotten "stuck". I'll leave it for a while still and see if it finds anything.
December 4, 2008 5:43:17 PM

I am having the exact same problem on my machine, with one exception. When I open task manager and look at processes sorted by CPU usage, there is always one process that is locked up at 50% CPU usage. If I end that process, the next application I touch and try to use will lock up, and show the same 50% CPU usage in task manager. I can keep killing the locked up process and the chain of events will continue to happen until I restart my computer. Everything I could find made it sound like one of the cores was failing. I was running an Intel D975XBX2 motherboard with an Intel Core 2 Duo 6600, but just the other day replaced the CPU with a brand new Intel Core 2 Duo E7300. For the last two days everything has been running fine, until this morning. The same chain of events has started, and the process that is locked up this time is iexplore.exe at 50% CPU usage. It is completely random when the problem will come up, and it is rarely started with the same process. I have tried everything I can think of, including updating firmware, drivers, and bios, with no success. Any help on this at all would be much appreciated.
a b à CPUs
December 4, 2008 8:21:36 PM

this is getting epidemic already. :?
could this be some new fancy virus or something thats spreading around the net?? cause I don't remember there ever being so many of these 'cpu at full tilt for no obvious reasons'-problems before...
December 4, 2008 8:30:18 PM

FYI, I am still have this problem but am learning to "deal with it" for the time being (I'm guessing until I reinstall XP).

I have tried everything besides defragging my hard drive, which is next on the TODO list (to be done probably never).
a b à CPUs
December 4, 2008 8:40:17 PM

there was this other thread in the forums where the OP had done formats and clean installs and it still was locking up because of some 'ghost' process... so don't get your hopes up :/ 

if it indeed is some wierd virus thats hiding somewhere safe in the HDD then maybe a new HDD could help lol
December 16, 2008 4:28:32 AM

Just want to add that I am having the exact came issue on an Acer Aspire One with an Atom processor.
June 15, 2009 2:54:40 PM

Add me to this list. I am running a quad core Q9400 on a Striker2 Formula with Windows Vista 32 bit; 4GB Ram, 1 T HDD SATA. 1 core would lock up at full and the whole system crawls. the disk would be blinking and would be spiking at 100% as well, observed this for 20 mins and no change, so i shut it down. Its ok after the restart. Any help would be much appreciated.
June 15, 2009 5:02:40 PM

magetpr said:
Add me to this list. I am running a quad core Q9400 on a Striker2 Formula with Windows Vista 32 bit; 4GB Ram, 1 T HDD SATA. 1 core would lock up at full and the whole system crawls. the disk would be blinking and would be spiking at 100% as well, observed this for 20 mins and no change, so i shut it down. Its ok after the restart. Any help would be much appreciated.


Open up task manager, go to processes, and make sure it's displayed processes from all users. Let us know which one is at or near 25% or higher. Remember that 25% cpu usage on a quad core is completly using one core.

July 10, 2009 4:35:43 AM

Same problem, Acer "Leviton 410". I know it's hard for those of you who haven't seen it, I wouldn't believe it if I weren't seeing it myself. 50% usage on *both* cores, in the "Performance" window, but "System Idle Process" at 95-99%, and nothing else ever above about 3% (and yes, I have "Show processes from all users" checked).

Very weird.

- rob
September 7, 2009 12:40:25 PM

Hi, has this problem been solved? This thread seems to just trail off with lots of people seeing the same problem but no one stating that it was solved. I am seeing a similar thing:

Core2duo E6600
2GB Kingston PC4200 RAM
Ga 965p ds3 MB
EVGA 8800 GTS (g92)

I get 100% usage on one core - but I always get the usage on the System process (ie "System" w/ user name "SYSTEM" w/ 50% usage in task manager). This has been happening for a few months now, maybe once or twice a week. I've just been rebooting.

Has this been solved???????

Edit: Also, the usage is 100% kernel (red) usage in the performance tab of task manager.
December 1, 2009 11:10:09 PM

Although this is not really satisfying, if you disable all but one of your "cores", the problem goes away. Performance is not all that bad. Stability is much better. Microsoft just can't figure out how to share a common memory with 2-4 processors. This problem is especially severe when multiple processors try to gain service from a single I/O driver.

So until MS catches up with Intel, go with one processor.
December 8, 2009 2:28:31 AM

I have had my computer for many years and it is dual core.

it just started happening to me tonight and i have run through the check list above, looking for something at 50, check the box, etc. rebooting only

the garbled sound was the giveaway.

right before it was happening, i went to run dvddecrypter, never happened the hundreds of times before. it locked before it ever got to read the dvd.

could not kill it. had to shutdown the computer. shutdown did not work all the way and left me with black screen with white cursor which i could control with mouse but nothing else.

pushed power button and went hard down.

on reboot everything appeared normal.

went to run dvddecrypter again and everything seemed fine.

then went to run another window as devdecrypter was doing its thing and noticed garbled sound. that is when i noticed the same problem above of one processor showing pegged at 100.

left dvddecrypter running and processor freedup and returned to normal when dvd decrypter was down.

just ran windvd on same drive and processor did not peak.

could be program problem, will reboot and try again and or reinstall devdecrypter. will advise.
December 9, 2009 1:38:54 PM

rebooted, reinstalled dvd... same problem.

one processor pegged and sound in other apps is garbled.
December 13, 2009 7:02:53 AM

Okay... so I read this thread because I started having the same issue today. After hours of running virus scans, installing spybot, etc. I still could not track down this "ghost" process that was eating resources. Task Manager did not list any processes running at >2%, blah blah blah...

Long story short- I did one thing today that changed the environment on this machine. I installed new drivers for my NvidiaGeForce 7600 GS card. Sound familiar to anyone else? So for tickles and giggles I rolled back the driver, restarted my machine and POOF! Problem resolved. I'm now back to running at about 0-7% CPU with 45 processes and IE open. Give this a shot and see if it helps. I'll check back in the morning. I'll count this one as a very frustrating win... but still a win.
January 20, 2010 6:08:01 PM

So I'm just a regular guy that happens to have experienced the madness you are going through about your dual or quad core. When one of your cores is at max or always 90 and 100 and yet you have nothing on. This maybe you noticed from your widgets on your sidebar and saw and said how the hell!!!! Well thrust me I did the same thing and went crazy looking for answers and answers on all different sites. I asked a friend on mine he knows more than I do and did the following to solve this issue:

1. I did the basic and got to my task bar and see what is causing this. You tried to eliminate as ending the process or the process tree. but you only see your core doing the same.

2. Ran a malware, spy bot, anti virus software's. Yes three different software's sometimes this could solve the problem do to bad sites and common things but I bet you did already and still the same thing.

3. So when and tried to download process explorer which is a good program and tells you all about your processing applications and programs and how much are they using etc.

4. Now What you though I'm going to system restore my computer to see if this works. Nope it did not right.

5. So you factory Restore now and had to erased all the things but you still see nothing has change your core still at 100. I know you are going insane now

6. This is the good thing you most likely you are like me clean and like to clean your computer well sometimes we tend to make small mistakes that gives us headaches.

7. Now if you don't have the proper material. I advised you not to do this because this is kind of risky. I'm talking about that your CPU fan needs to be align correctly and when you disturb the position of it by moving it a little bit like cleaning the inside of your computer and you have a mid-tower like me, this is the main cause why your core is giving you a high reading. To solve this you going to need uninstalled your CPU fan and while you at it you can uninstalled your CPU for resetting.

8. Now if you don't know what I'm talking about on step 7 I advise you not to do it because you can really damage your computer. But I assumed you know your CPU and You know your fan. So what you will need now and is up to you is an anti-static band they cheap cost like 12 dollars but you also going to need a thermal cooling compound paste that is installed on the CPU a little bit but in an X mark of the CPU fan to keep the CPU from overheating.

9. Have in mind that this process needs to be done quietly because while uninstalling the CPU you decide to watch a movie or playing a game, I hope you live alone because we are talking about your computer here and the main part of it your CPU. That is why I suggest you get cautions like getting the anti-static band because you can easily burn the CPU with static and now you don't have a computer. I hope this works out as it did for me. any questions feel free to ask.
a b à CPUs
January 20, 2010 6:22:44 PM

armand2816 said:
So I'm just a regular guy that happens to have experienced the madness you are going through about your dual or quad core. When one of your cores is at max or always 90 and 100 and yet you have nothing on. This maybe you noticed from your widgets on your sidebar and saw and said how the hell!!!! Well thrust me I did the same thing and went crazy looking for answers and answers on all different sites. I asked a friend on mine he knows more than I do and did the following to solve this issue:

1. I did the basic and got to my task bar and see what is causing this. You tried to eliminate as ending the process or the process tree. but you only see your core doing the same.

2. Ran a malware, spy bot, anti virus software's. Yes three different software's sometimes this could solve the problem do to bad sites and common things but I bet you did already and still the same thing.

3. So when and tried to download process explorer which is a good program and tells you all about your processing applications and programs and how much are they using etc.

4. Now What you though I'm going to system restore my computer to see if this works. Nope it did not right.

5. So you factory Restore now and had to erased all the things but you still see nothing has change your core still at 100. I know you are going insane now

6. This is the good thing you most likely you are like me clean and like to clean your computer well sometimes we tend to make small mistakes that gives us headaches.

7. Now if you don't have the proper material. I advised you not to do this because this is kind of risky. I'm talking about that your CPU fan needs to be align correctly and when you disturb the position of it by moving it a little bit like cleaning the inside of your computer and you have a mid-tower like me, this is the main cause why your core is giving you a high reading. To solve this you going to need uninstalled your CPU fan and while you at it you can uninstalled your CPU for resetting.

8. Now if you don't know what I'm talking about on step 7 I advise you not to do it because you can really damage your computer. But I assumed you know your CPU and You know your fan. So what you will need now and is up to you is an anti-static band they cheap cost like 12 dollars but you also going to need a thermal cooling compound paste that is installed on the CPU a little bit but in an X mark of the CPU fan to keep the CPU from overheating.

9. Have in mind that this process needs to be done quietly because while uninstalling the CPU you decide to watch a movie or playing a game, I hope you live alone because we are talking about your computer here and the main part of it your CPU. That is why I suggest you get cautions like getting the anti-static band because you can easily burn the CPU with static and now you don't have a computer. I hope this works out as it did for me. any questions feel free to ask.


Kinda late there. :sarcastic:  "looks at dates posted"
January 20, 2010 9:27:55 PM

I know but as I was doing research online on this issue many good thoughts came from so I'm just giving out my two cents of help to anybody that needs it out there before they beat their computer up and what best place to do that then tomshardware
January 25, 2010 6:21:09 PM

Hello every one i know it’s an old post but........

i have has the same problem AMD phenom 955 3.2ghz standard (3.8ghz overclocked) 8gb DDR3 ram 1TB HDD windows 7 ultimate genuine (free copy from micro$haft), i have seen the same problem but every so often it would jump to a different core :S so thought nothing of it phoned AMD and they didn’t know sooo thought nothing of it. there i am on my laptop 3-4 days later and it almost grinds to a halt that also running windows 7 ultimate that only 1 core Intel m 2gb DDR2 at this point I’m thinking it is too odd now I’m checking all my processes like mad on my laptop found iexplorer.exe running it to full but when i ended the task it did not close anything down which was odd so i opened "msconfig" through the run bar and looked at start up processes and there was a taskhost.exe running from within my user/appdata/temp which was odd and publisher unknown so i disable it ok that and it was fine after that. went to my big computer and saw there was not taskhost.exe but there was an apocalypse32.exe running and it was directly from c:/windows/ so disabled that and deleted the file and after that it is fine :)  just check your task manager see if there is anything odd if not look for things that should be there but are not behaving end them it doesn’t throw up an error get shot and see if you can see anything in msconfig that shouldn’t be in the start and that is running from an odd location like your temp file or direct form c:/ windows and is not by any known manufacture.

Hope this helps all the people with naughty CPU’s and have fun disabling stuff :)  don’t worry even if you disable all the start-up tasks your computer will start up for don’t be scared.
October 24, 2010 12:03:38 PM

Another late post, but thought i'd post an additional note to sralph's suggestion re. disabling cores - I had similar problems for months on my HP nc6400 laptop. After trying traditional troubleshooting techniques (disabling processes, uninstalling software, checking msconfig, disabling antivirus, etc.) I decided to abandon microsoft completely (always a wise move) and install Linux Mint, which is ... well, mint!. However the seizing up issue returned, which drew my attention immediately to the hardware - sure enough, disabling dual core mode in the BIOS resolved the issue.

I suspect that dual/multi core systems are very prone to overheating due to inadequate cooling, as my locking up issues occurred only after the PC had been on for a while - so naturally disabling one of the cores is the solution. It's just a shame we've all been suckered for yet another technology that doesn't fulfill it's promise - I reckon PC manufacturers should recall PC's just the same as cars if they are not fit for purpose (although I agree there isn't the same safety issues at stake).
Anonymous
a b à CPUs
March 18, 2011 7:55:54 PM

FIXED!!!!

It was the NVidia driver for my 8800GTX. I downloaded and installed new driver. It asked if I wanted to clear the old driver settings and completely uninstall the old one, which I did.

All four cores now reading the same. Core 1 no longer sticks at 100% after 1 day of running.
September 25, 2011 10:55:51 PM

!!--Problem solved--!!

I think it is amazing that I'm reading information from 2 years and older. But I want to report back to you the same resolution. Problem solved.

I recently had the Exact same issue. Here are my details:
AMD Athlon 64 X2 Dual Core 3800+ 2.00 Ghz
4GB Ram
ATI HD 4800 Video card

My computer continually would run between 50%-80% usage during idle. After looking over CPU usage history it showed 1 Core being used the entire time. No Processes were causing this.

Finally I took the advice of Rolling back my Video Card driver from 7/2011 back to 9/10/2010. This resolved the issue.

My Wife was continually blaming Blizzards Starcraft II that I had installed a few months back. The PC would Suddenly Freeze and Reboot, giving some weird "Send to Microsoft" errors. We would be trying to watch a Movie and it would reboot 3 times throughout the movie.

I uninstalled Starcraft II, but it didn't fix it. Finally today, rolling back the drivers made me realize that Starcraft II prompts you to download the most recent drivers for your Video card....


Unbelievable that Updating drivers can cause this issue..

ANyways.. thank you Tomshardware.com and thank you all for posting here..
!