Slow computer and high CPU usage? A possible solution


Posts: 5,746   +14
CPU Maxed Out?
There's probably something amiss.
Lincoln Spector
Tuesday, December 28, 2004 05:00 PM PST

I recently received the following question from April Turkett of Morristown, Tennessee.

Two days ago my CPU usage jumped to 100 percent, slowing the computer beyond use. Any ideas on what happened and what to do about it?

An overloaded CPU can make a PC unbearably slow. If the CPU spikes happen rarely and correct themselves quickly, don't worry about it. But if they keep coming back or don't go away, you have to find out what's wrong and fix it.

The most obvious culprit is a virus, spyware, or some other malicious software. Scan your system regularly with a good spy-catching program such as Lavasoft's Ad-Aware or Patrick M. Kolla's Spybot Search & Destroy. They're free, so why not download and use both of them? Next, update your antivirus definitions and run a full virus scan. Set your antivirus program to check for updates and do a full scan automatically at least once a week.

If virus and spyware scans don't find the problem, it may be due to a malware program that's too new to be caught. More likely, however, is an unintended problem with an honest program.

If your system's CPU spike is constant, the software at fault probably loads when Windows boots. Select Start, Run
, type msconfig, and press Enter. Click the Startup
tab, uncheck suspicious options one at a time, and reboot until the problem stops. Windows 2000 lacks this utility; for this OS, download Startup Control Panel, Mike Lin's free alternative.

If the processor overload occurs intermittently, note what you're doing each time the system slows down: the programs you're running, the Web sites you visited that day, and so on. This information may give you a clue.

In Windows XP and 2000, the Task Manager can show you what's chewing up CPU cycles. Press Ctrl-Alt-Delete (in Windows 2000, click Task Manager
). Choose Processes
to see your running programs and subroutines. The CPU column shows the available CPU cycles that each process is running. You can easily find the problem here. The Performance tab shows your CPU usage. Hover the cursor over the Task Manager icon in your system tray to see the current CPU usage in a pop-up window.

Keep the System Idle Process running, even if it's huge. This process shows the percentage of CPU cycles that are not in use, so in this case, the bigger, the better.

Once you've found the processor glutton, get rid of that program. If it's something you can't do without, determine whether an updated version with a bug fix is available, or look for a competing program that does a better job.


Posts: 180   +0
For those of you with issues where you get 100% cpu usage on startup for a couple of minutes, the culprit is most likely windows updates. Disable that (use manual only) and your boot-ups will be much, much faster.

wanna be geek

Posts: 77   +0
Type msconfig into the run box, go to start up and disable everything, reboot... If it doesn't happen repeat and enable one item at a time...


leave your system ALONE until you have reason to indite (ie blame) a process.

use your Task Manager-> Process Tab
click on the Column Heading CPU Twice

the processes that use the most cpu will always be at the top of the list.
System Idle Process should be on top, but if you've really got a bugger in the wood pile, it may not be.

Watch for several seconds and you will get a list of suspects to investigate :)

wanna be geek

Posts: 77   +0
No offense "Jobeard" but how can you say "leave your system alone until he has a reason to suspect some app is at offense?" If I read the post correct everything was fine til a day or so ago... There is nothing wrong to go into msconfig and disable all and boot up. You can do this and do a elimination one by one til the culprit pops up... You are in NO way harming Windows or you OS in anyway.....
In fact when running XP, the only start up that will show after a clean install is CTFMON..... After that it is all user installed... So how can that screw things up???


msconfig has the power to really mess you up if you start disabling services and startups manually.

the right way to use it is the /SAFEBOOT switch on the Boot.ini tab;
leave everything else alone.

when you've fix the problem, you can revert to Normal Mode and all your startups and
services will be as they were before you started having problems or fussing with msconfig.

wanna be geek

Posts: 77   +0
Ok, once again I will ask you... How does it mess you up??? be specific- Oh, I guess you can't because you don't know.


goodness me.

specifically, you can disable a service or startup you need or want and forget that
msconfig has disabled it.

please, I have no need to fuss with you -- it's all depends on what you want to do.

I guess 'wanna be geek' has very deep implications ...


Posts: 2,854   +200
Advanced Task Manager is better to use and you can monitor what's going on..






You cannot break anything by unchecking all of the startup tasks in Msconfig, but Msconfig should not be used to disable services. To do this run: "services.msc".

It is far better to check out the tasks you are actually disabling first of course, by goodling them and it is also wise to check the cpu/memory usage of running tasks by doing:

tasklist /svc

from the terminal.

This will show you everything including the processes running under svchost.

@tipstir: That looks like a good program.


Posts: 12   +0
Sometimes firefox robs 90% of my CPU & uses 180mb of ram with a few tabs open. im guessing thats not normal? I have 1 addon, & is called foxclocks. ny suggestions or advice on whether FF is ating normally is appreciated :D


Posts: 1,364   +4
I believe that Firefox preloads all webpages that your current tabs have links to. This is to allow you to navigate to these pages faster. But sometimes that function uses a lot of memory.
BIG Possible Culprit!

Make sure your Bookmarks Toolbar is turned off. This drove me crazy until I figured out that this was my main culprit for spiky CPU usage.


Posts: 777   +139
I've use Task Manager to end process on several programs and also used Selective Startup Mode to see if any of those are making my computer run slow and none of them resolved the issue. I just threw my hands up and co-opted my wife's computer. She doesn't use it that much anyway. :p
Had the same problem: 100% CPU and slow computer. Culprit: overheating!

I had the same problem.
CPU stuck at 100% and computer driving me crazy.
I checked all processes and applications to no avail.
Finally I noticed in TASK MANAGER (CPU usage) that maximum frequency was stuck at 33%. Usually that has to change dinamically to accomodate processes. To make it short: when overheated, my laptop protects itself by setting the maximum frequency to a fixed value (in my case: 33%).
That forces the CPU to reach 100% even when few processes are running (I initially blamed the PID 4 process since it seemed to take all the CPU).
Probalby my fans are not efficient as they used to.

The only remedy?
Unplug the power supply and run on batteries.
After 3/4 minutes I noticed that maximum frequency was happily jumping up and down and performance became acceptable again.
Not much of an intervention (I dislike plugging and unplugging) but it works.

Hope it helps.


Posts: 326   +13
guidosim - yes, protective limiting of cpu

guidosim - yes, cpus have a built-in dealio that limits them when they operate to hot;
you should cool the cpu better, and / or figure out what is causing it to run all the time, if it is.

generally, a computer, incl laptop, should be able to run above 33% steadily if cooled decently.

my l;aptop overheats if it cannot breathe on the underside - like if I set it on a pillow while i am sitting on the couch.
I have spent weeks trying to resolve the same problem. Today I have obtained a new power cable and Eureka, problem solved. Apparantly there is a setting somewhere (maybe the bios) that causes the cpu to compensate for loss of power and having a damaged cable caused this. Worth a try before spending weeks trawling the internet for a solution.
I have read all of the posts and my problem is similar and dissimilar at the same time. My computer is running slowly all of a sudden. My flight Sim's graphics are slow and jerky. When I went to Task Manager it shows that WAOL is over 311,000, the largest mem usage. In performance PF usage remain stable but, CPU usage is bizarre. As it scrolls, it jumps to 100 moves 4 bars and drops to 0 for one bar then jumps back to 100 for an additional 4 bars then drops to 0 again. It just repeats this with no veriation. I have never seen this before. Any and all advise or info will be greatly appreciated.
I have a problem, I did what was said and my CPU is still maxed out, some programs, svchost.exe and Windowsmediaplayer_codecs.exe use up my CPU, I disabled them and they come right back within 15 seconds. Please help me..


Posts: 6   +0
One other thing to check for, and this happened to my last computer, is to make sure that your core voltage is set to the CPU recommended setting. I had an ASUS mobo combined with a AMD Phenom II X4 and after about 3 or 4 months, EVERY time I rebooted my PC, the system would always override the Vcore voltage to unstable levels. I had to download ASUS PC probe II to manually stabilize my Vcore. I can't say what was to blame, but since upgrading to an 8 core FX with the same MB (and an updated BIOS), the issue has not re-occured.
THANK YOU SO MUCH! holy crap who knew that a faulty freakin power chord would be the problem....(took far too many man hours of program/system research and two clean installs and finally reading your comment to figure it out)
I suspect that I have some malware in my PC and I would appreciate some advise from techspot wizards. For some days now, my old PC is showing 100% CPU usage and is painfully slow. So slow that is now practically unusable. I saw in the task manager that there was a process hogging 50% of the CPU and I ended it. Then there was a process that was idle and started hogging 50%, once I terminated the other process, meaning that CPU continues working at 100%. I ran Advance System Care, for almost a day and it didn't improve, then I ran Iobit Malware Malware Fighter, which didn't detect any malware. I've ran (partially) the anti-virus (Avast Free Edition) because it was taking me another day and it seemed to be frozen at 60%.
Up to now, I don't see any improvement in my PC. Any ideas what to check or if there is any other software that I should try in order to detect if there is some hidden bug there?

Thanks a lot for your help.