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Why is my CPU running at 100 percent, when only three windows are open?!


Windows XP: Why is my CPU running at 100 percent, when only three windows are open?!

I run Windows XP (Home Edition)on my system and frequently find that the number of processes running can be as high as 63, with the CPU usage rising to 100 percent and a commit charge of 943M/2313M. I should add that this happens with only two or three windows open but minimized.

This completely takes over my PC and virtually brings it to a non-useful condition. Can anyone please tell me what can be done to help me safely bring the amount of processes down as I don't believe that all 63 are needed? Many thanks and kind regards.

--Submitted by Patrick N. , London, United Kingdom

Here are some featured member answers to get you started, but
please read all the advice and suggestions that our
members have contributed to this question.

Troubleshooting a slow PC --Submitted by Droid

Why is my CPU running at 100 percent --Submitted by Fatboy71

Runaway processes... --Submitted by Wolfie2k5

Check your processes & scan for viruses --Submitted by si

Try an "empty" start --Submitted by TreknologyNet

CPU at 100% running answer --Submitted by seking0011

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Why is CPU at 100 percent when only three windows are open?

At home I have 73 proceses running and with the extra security at work there are 84 processes running. While so many processes may slow down the system a bit, it is not objectionable. I can still run Roxio Creator to edit videos.
Use task manager to determin what task is hogging processor time. There are Five possible problems:
1 A security (virus etc.) program is running continuous scans, if so delete and reinstall the virus program.
2. You have some malware operating continuously. Run Adaware and/or Spybot Search and Destroy.
3. Your system has too much trash. Run CCleaner to clean all temps then run the CCleaner registry cleaner.
4. This problem can also be caused by a memory fault, but this is rare. Run a memory test program to eliminate a hardware memory problem. I had a ram SIM develop a bad bit and cause this problem.
5. You have a have a software fault on the hard drive. If all else fails you must save all of our data and reinstall Windows. The disk can fail such that it is trying to repair corrupted data. The disk then runs continuously. I have seen several systems develop this problem. The solution is painful, but the reload has worked every time the previous easy solutions failed.
Bruce L.
Johns Hopkins U.

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An extra note on "bad sectors".

I'm sure there is a Registry Entry that would fix this in multiple versions of Windows:

Are you sick of seeing "Attemtping to recover Allocation Unit ******"? 10 times on each disc error? All this does is slow down the formatting process.

Is there anyone out there who has seen such a "recovery" actually succeed? I remember when setting up Novell Servers that one used "Comprehensive Surface Analysis", and this was only on 20MiB drives! This program would run for days doing sequential and random access to every sector on the hard drive, and it only took one failure for the sector to be marked bad. It may have seemed a week's waste of bench-space and electricity, but it sure contributed to the ultra-reliability of Novell's early servers.

So, additionally (and without straying too far off-topic), if anyone out there knows of a Registry Entry in XP and/or 98SE that by-passes this attempted "recovery" and just marks it as BAD first time, I would be grateful.

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No such thing.
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Not surprised

That is precisely why I asked the question here, because searching down every minute Registry "detail" is usually futile.

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use this

this also happend with e then i use cc cleaner when windows starts this help a lot try this may be it help you

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Use the control +alt+delete combination and check

When you punch these keys together you access the task manager, there you can check which programs and applications are running, and there is a menu in the task bar that allows you to select wich are the programs that run when you log in.

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Fight Back! Control your running programs

Firstly, you want to make sure you have enough RAM that is Working. Sometimes an older machine will have RAM (bad chips, physical damage,overheated, and the like) that isn't working. You can check this also with the Administrative Tools. Sometimes your swap file to the hard disk has been disabled, or the processor has been re-clocked to an incorrect speed, or there's malware sending your CPI and footprints to The Tanzania Republic, and all that, but these are pretty rare.
Other than that, it looks like you have the infamous background running processes problem. I don't like to Name Names, but a certain imaging program has an AIR process that can freeze older machines. You are going to have to Inventory your running processes and figure out which ones are essential and non-essential for the health of your Heatsink and Processor.
As you may or may not know, we find that file and services sharing on Networks can do this to you as the Your computer or others on your Network communicate. Processing your threads and everyone else's can consume resources. This is pretty rare.
I would tick off the Marketing departments for all those background running programs and shut off what you don't need.

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I think u should increase ur ram.

Try a ram of greater size than the old one. I think this will help u.

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Welcome to the Malware Wars!

You are probably infected with one or more viruses/malicious software programs (and possibly a Trojan or two). First please understand that the removal process will not be simple and will require reading, following instructions and using all of the patience that you have and then some. First I suggest downloading Anti Malware. Available from cnet @

Remember to read the instructions and pay attention. This can save many hours of frustration.

You can also try HijackThis! by Trend Micro - it is also free and you can upload the logs it will generate to multiple sites to get help with your system cleansing.

After you clean your system there are several steps you can take to prevent this in the future but probably no one piece of software will prevent a system infection completely.

Check out these 10 Steps to Malware Prevention.

You could also pay someone to clean up your system for you (just don't pay by the hour! LOL) but going through this process will actually make you more aware of what should and shouldn't be running on your system making you a much more savvy user and less of a target for the more insidious denizens of the web "deep".

Finally, Good Luck.

Lee Herrin

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3 possible solutions

A you have spyware or anti virus eating up your cpu resources

B you un installed some anti virus program in the pst and when you install the new one thy are conflicting

or C which is the most likely one but also the hardest one to fix... as you stated you run win xp home and their were two old updaates that you haave to check for and maybe un install them ( 1 or both ) but you will need to find the update numbers on microsofts knowledge base
you there search function and it might make it easier to find

hope this helps and good luck

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So many possibilities....

I have had this happen on at least a dozen of my PC's in the last couple years. It also all depends on the type of PC, Processor and amount of RAM in your system. Checking your startup programs and processes and cleaning your system, including ridding your system of unneeded files is always a good start. Anti-Virus and Anti-Spyware programs are quite hard on the processor, so make sure they are not doing scans while you are attempting to use your computer. Possibly switch out Anti-Virus programs if this in an issue. Also Anit-Virus programs will fight against one another if more than one is installed at a time. Another issue I had was a Hard Disk Drive issue. On a Cicero 4130, P4 1.6Ghz, 512MB DDR Ram, XP Home SP2, last year, it became almost impossible to log on. I later found out that the Hard Drive (40GB Western Digital IEDE PATA) was seriously lacking on Read Speed and was about to die. This caused my CPU usage to soar through the roof and make the computer unusable. Just about anything is possible. Good Luck.

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CPU at 100%

It could be lots of things, but be careful when installing programs, when it asks you about automatically updating and sending anonomous data beware!! They will run whenever they want and you're at their mercy.

One other thing that happened to me, I THOUGHT my hard drive was spinning up until I finally took the cover off my computer and found the processor chip totally covered in dust and lint which caused the chip to heat up and the fan on the chip to turn on ( a lot!) blew out the chip and cleaned the fan and it worked like a champ.

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Printer Driver Issue?

I had this problem with an HP printer on the network. The program to find the IP address took 100% of the cpu if the printer wasn't turned on. Real useful.

To find it. I used Task Manager, Cntrl Alt Del, Task Manager. Then select (Double Click) on CPU twice to put processes using your CPU at that top of the list. Then for HP it was a dll program running, so this is more complicated as I had to find out how to determine what dll was running. I believe it required a dos shell (Start Run CMD), then a command to list the dll processes, then I deleted the hp process using task manager and reran the dos shell command to verify that that process stopped. As cpu usage returned to normal that tells you which process was hogging the cpu. Then you go to manage your computer, processes and set it to start manually instead of on startup or automatic. Hopefully you don't need it. For me I uninstalled my HP print driver and put it back on a usb port. Its been over three years and HP hasn't fixed it so its never going back on my system. I don't know what people on portable laptops due to access HP printers on a network when the network isn't there which is the point of a laptop.

If you have a dual core machine you might see 50% cpu usage indicating that one processor is running something forever. That's a waste of your time too. So you really need to check into what's causing that to happen.

I also don't know what normal people do. This took me a couple of evenings to fix and search on the web to find solutions and how to lookup the active dlls. Sorry I don't remember all of the details but I DON'T WANT TOO. Software shouldn't auto update, and dlls shouldn't be called and run by themselves, and auto starting apps should be outlawed. Leave my system alone thanks. I once had Fedora Core 4 running with no changes for 8 years. I only updated it as my bank required a version of Firefox that I couldn't get as my OS was too old. Win XP with antivirus is much slower.

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Printer Driver Issue?

I had same problem. It was on a HP 2.8G P4 system with 'Hyperthreading'. It seemed that the hyperthreading was the problem. Another system without hyperthreading did not have the problem.

So, I went to ControlPanel->Printers, selected the printer properties to find the address. Next put that address into the browser and got a printer control interface. Click 'Networking'. Change the setting to a manual IP address of your choosing. I used one above the DHCP range (but less that 255), set the network mask, set the dns servers. Next, on the 'Advanced' tab, set the type of security on your local network. Then save these settings (OK a warning about the config).

Now reboot your system. This will let the guilty program set the printer address in the printer properties.

Now run 'services.msc', find the HP process that says it finds devices, right-click the startup and set it to manual. The program is not needed if the printer has a fixed address.

Shutdown, power down the printer, turn the printer back on, and then boot the computer. It should work and the CPU% will not be running high. I found this fix on the net using Google.


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Why is it running slow

Besides software, malware, spyware and all of those fun things it could actually be type of processor. If you have a single core processor with little or no cache. You would be amazed with even a jump to a dual-core or now we have quad(4), hexa(6), octa(Cool and a 12 core cpu. It is just amazing how technology changes so fast.

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If not printer driver then possibly Antivirus...

Beside the printer driver looking on the network to discover the IP address of a printer turned off, I've had AVG Antivirus running a full disk scan on boot up. This really slows down your machine if you only have a single core cpu.

To find this, do the CNTRL ALT DEL and pull up your Task Manager. Select the processes tab. Double Click on CPU twice to put the most active process at the top of the list. If its an AVG process then that's your problem. You could wait an hour and see if it stops. Or uninstall AVG and install AVAST and you should be golden.

For some reason AVG thought it would be really smart to make us wait after booting the PC to check the complete file system. NOT. Nothing should get between me and my PC. It should always respond to what I want to do today, now, this nanosecond and not something else.

I suppose AVG thinks everyone is running Quad Core systems and using 25% of the CPU to scan on power up is okay. But most of us have old obsolete systems with minimum RAM and have to deal with SW that continuously updates and takes control. Give control back to the owner of the machine. You didn't pay for the hardware, nor the network connection, nor the electricity to power it up, so let the user use his own PC they way they want. If I want to power off when I'm not home or online 99% of the day then I shouldn't have to wait for a complete antivirus hard disk scan to enable me to check my email or peruse the internet or check on my Volleyball schedule.

I really would love a machine with no updates. NADA. No way to infect me or cause me to not be able to boot up and go online. What's so hard about that? The closest I can come is an UBUNTU boot disk. But then I can't save anything.

Even my phone updates. But that's another story.

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printer driver issue.`

I've use AVG Free for over 10 years with no problems. It auto updates. I set it to scan at a time when I'm not on. My DELL printer died. So I plugged in my HPPhotosmart C4780 that was on my laptop. It loaded up OK. I use it 2-3 times a week.

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Good Point, but I have found not always the case

Its very true how a Dual/Quad or otherwise processor makes a ton of difference, I found that out in 07 when i bought my new PC, yet for everyday computers I still run many from 01-05 all with single core processors from 1GHz-3Ghz and for most computing they still work just fine. I find as long as your programs are not overly processor hungry and the system has at least 1GB of Ram for todays computing, (2GB preferable) older computers still work quite fine.

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I have found TV Guide uses 50 % plus of my CPU.

I have found TV Guide uses 50 % plus of my CPU. More than, Exporer, Word, Excel, Outlook, and outlook express all runing at the same time.

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Dual Core PC at 50% = Stuck Process.

If TV Guide pegs your processor at 50% and you have a dual core machine then you too have a stuck process sucking the life out of one of your cores.

Do the Cntrl ALT DEL find the process and eliminate. Then figure out how to turn if off.

Just four stuck processes will peg your QUAD CORE Machine. I can see it happening now... Oh but will be at Oct Core machines by then so no one will notice. Wait we're already at eight core machines...

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I have Windows 7 OS with Microsoft Works 2000, version 5.0.

In Task Manager, I found WorksCal.exe running, using up 45% of CPU, causing CPU to run at 100% continuously. Now, I downloaded Windows Installer and uninstalled Microsoft Works and seen that it's gone and non-functional, but I'm still seeing WorksCal.exe popping up in the Task Manager each and every time I click on "end process". It just WON'T go away!!!!

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Possible solution

Hello. I'm new to this forum and hope I can contribute. I have XP Media Center and I was the same thing happened almost 100% CPU. What I did was verify that processes were active and observed that, after having used and closed Windows Media Player, CPU fan spinning at high speed and therefore was very hot and the air began to be dismissed slow PC. Using Ctrl + Alt Gr + Del, select from the Processes tab and saw wmplayer.exe was consuming 50-55%, despite not being active any music file. The selection and gave End Process. Done this, the CPU usage under up to 30%, which is what was actually used with some programs running. I recommend you try closing the programs that are consuming too much, except explorer.exe. I hope this is helpful contribution. Regards

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Why is my CPU running at 100 percent?

I found a program called TaskInfo 9.x at (free for 30 days) that's like Task Manager on steroids. On my HP Windows MediaPlayer caused OSD.exe (On Screen Display) to grab all available CPU usage and not let go, and even when MediaPlayer was closed, it was still open. I could use TaskInfo to close MediaPlayer, but I went to StartUp (in the Run window, type msconfig and go to Start Up tab) and unchecked OSD.exe. I don't know why the two programs conflicted, but this workaround allowed me to open and close MediaPlayer normally. If you find a similar conflict, maybe you can find a suitable workaround as well.

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Why Is My CPU Running At 100%?
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It has happened to me.

When it first happened I assumed a virus...
My experience has been though, it happens because of otherwise benign processes decided they wanted to check for updates at the same time.

A reboot generally reschedules updates and the problem goes away for a time.

Keep an eye on processes running though. They should be consistent update to update. Otherwise you have to worry about virus'

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insuficient RAM

maybe your RAM(Random Access Memory)too small...or maybe you using heavy program such as adobe premiere on 1GM RAM...on the 1st page of replies i think AV(Anti Virus)program doesn't count.coz it take small amount of RAM(i think[about 15-40MB RAM])..
and the other problem is your harddisk too full(contain about 75%up),youre using the drive C:// to save your data,game,etc.
if the drive C is too full,where you save the cache?and the paging file that windows use??
i recommend you to delete or moving the data to another drive such as drive D or else..

if you have more budget,maybe you can upgrade you PC..if you think its worthy.

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Why is my CPU running at 100 percent, when only three window

Well, I have a PC whose motherboard can handle only 500 MB of memory and is full of applications, but it runs as smooth as a clock!

I have removed all unnecessary startup items using MSCONFIG and also made sure there are no unwanted items in the Startup folder that are surreptitiously installed, such as the MS Fastfind.

I also have been using Ashampoo Magic Uninstall on all my machines. This keeps my registry lean and mean. Believe me, none of those registry cleaners work. At one time, I used to use 5-6 different registry cleaners to consecutively clean the registry. Many times, after I did that, I still found debris in the registry from uninstalled programs that I know should have been removed.

Maybe, that is why my 730 MHz 512 MB RAM PC still runs all those programs over Windows XP Professional!

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about the registry

NEVER EVER ever!dont ever clean up your registry..coz that may have delete the essential part of your OS!except you understand what you do and what are you deleting..
i have some experience about it...i mistakenly delete my important registry...i learned from that..some program stopped i re-install my OS...never ever do registry clean up if you dont understand what are you doing...that it

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response to " why my computer is running at 100 percent

I remember having those problems a couple months ago, almost made me not even bother with getting on it. I did something similar to what you said in that newsletter. Instead shutting down processes, I went to the services and began disabling services i never use, and manual activating the ones I use every now and then, and delaying ones from start-up.

Works pretty good for me. With only 1 GB in my computer, which has vista; moves just about as fast as a computer with 2 to 3 GBs.

I can list the services I disabled if you want. Send me back a message and I'll send the list.

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Several things to fix a slow running computer.

I would say the first thing for this specific situation hardware wise is RAM. You have what looked like 2 gigabytes, install 2 more gigabytes for a total of 4. One thing specifically to note is windows XP (or generally any version which is not 64 bit will only tell you it recognizes an amount just over 31/2), but that is just what the OS is able to recognize, not what is actually running.

The next think I personally would do would be to run Spybot S&D make sure you have the real thing as a lot of things will come up when you search for it. That is because everything good and bad or at least a large number put it in there description because a lot of people get this recommendation. Either way download it and run it fully, then delete everything which is not from Microsoft.

The next thing I would tell you would be to hit windows key then run MSCONFIG, and look at the startup tab, and take the check out of everything you do not want to run at startup which is not from Microsoft. Do not change anything unless you understand what you are doing, Google Bing or Microsoft website directly can all be your friend here. Then restart your computer, and hit start choose all programs/accessories/system tools/disk cleanup, Choose your main drive which in most computers is C: and put a check mark in every box and hit start. Following this defragment your main drive completely. (defrag is also in system tools)

If you wish to go further go to
tweakhound also has guides on Vista and Windows 7 and Linux. Again only do what your comfortable with, and or understand. He explains very well and his guides are tabbed per user experience levels as well. You can also buy a copy from him which may be a very good idea especially if you are not very familiar with work at this level.

Then following this make sure you run Spybot S&D monthly, do disk cleanup, and defrag as well once a month unless there are mitigating circumstances. The first of these would be if you have an SSD as a hard drive as SSD drive do not need defragmentation per se, and it can damage them or at least your data.

Please follow these steps in order if you use them. I can pretty much guarantee you your PC will run better.

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