V. high CPU usage

[Amp34]

I'm not sure if this is a hardware or software issue so am going to stick it in here.

Recently my sister has been complaining her computer was unable to do simple tasks like play BBC iPlayer, music and being generally slow. Looking at the task manager it appears the CPU is at almost 100% most of the time and the visible processes don't add up to anywhere near the total (have show proesses for all users on).

Fans appear to be spinning and temps seem fine (54 ish with almost 100% usage) so I assume there is no heat problems. It's fills me with a little bit of dread as my parents PC has almost exactly the same problem and I've never managed to sort it out (including formatting and reinstalling the OS).

My only other ideas are either an incompatability with the hardware (unlikely considering it was built over a year ago and was fine up until now), hardware failure or a root kit?

Anyone have any other ideas that I can try, bearing in mind they will have to be to acted over the phone to a not very computer (hardware) literate person as I'm a few hundred miles away from her.

Thanks

 

[StephenLawUK]

if you have indeed done a full reinstall before and the problem persists i doubt it is a rootkit.

How many processes are showing up in Task Manager? I know if you buy a PC from the shops they preload lots of stuff onto startup and that run in the background and when you then install your own stuff will slow your PC's performance.

1st step run an full antivirus and spyware scan.

Then try
Start > Run > Type msconfig
click the startup tab then use google to find out what each part is and decide if you need it running or not and disable/enable as nessesary. If you cant find out what something is its best to leave it.

And lastly
Then go to control panel > Administrative Tools > services.
use this guide to help disable some of the unwanted windows services
http://bloggerdigest.blogspot.com/2007/01/disable-unwanted-windows-xp-services.html
if there are entries that you cant find on there google them again and disable/enable as nessasary. Again if in doubt leave it running.

If that doesnt help im not sure what it could be unfortunately.

 

[EsaT]

Rule number one of tech support:
Don't tell hardware/software configuration - That's for what we have crystal ball.

If problem appeared suddenly it sounds like either Windows is crapping out or it has been infected.
Hardware problems would cause errors/crashes and I don't believe that HDD dropping to PIO mode could cause that high CPU load.

It's fills me with a little bit of dread as my parents PC has almost exactly the same problem and I've never managed to sort it out (including formatting and reinstalling the OS).

Brand PC?
Reinstalling OS from recovery disc won't remove shovelware.
(also with bridging internet connection PC can get infected before installation is complete)

 

[Amp34]

I was going to post the specs but then decided against it for some reason...

Anyway specs are as follows, from here:

Intel Core 2 Duo E6320 "LGA775 Conroe" 1.86GHz (1066FSB) - Retail
Corsair 2GB DDR2 Value Select PC4200 Dual Channel Kit (2x1GB)
Hitachi Deskstar T7K500 NCQ 250GB SATA-II 8MB Cache - OEM
Antec NSK1300 ATX Cube Case - 300W PSU
Samsung SH-S203BEBN 20x20 DVD±RW Dual Layer Serial ATA ReWriter (Black) - OEM
Abit Fatal1ty F-I90HD ATI Micro ATX (Socket 775) PCI-Express DDR2 Motherboard
Microsoft Windows Vista Home Premium 64-Bit Edition DVD - OEM - 1Pk

I built this PC about a year or so ago so no bloatware on it and my sister is reasonably good at not installing clutter (did the usual msconfig clearup after installing the necessaries so it should be a pretty tight ship).

I don't know how many processes are open (probably about the usual 50-60 of vista, but i'll check next time I speak to her) but I got her to tell me the combined total of cpu usage of the visible processes, whch was about 10% (so the usual). That's the bit that completly stumps me, it would appear there is something cpu intensive using the processor (from the task manager stating 100% usage and problems with anything remotely intensive) but not showing in task manager, or there is a hardware problem, but as you say EsaT if it was hardware it would generally come up with errors, and her computer is fine in that department, which is why my first thought was overheating and throttling.

It does seem to have come on suddenly, about a week ago, and from her comments was perfectly fine before that. I got her to do an AV scan and negative (hasn't been connected to the net for the last few months, although that doesn't rule out memory stick transfer.

And thus is why im stumped If I can't sort it by easter she wll bring it home and i'll reinstall the OS, but from past experiences that probably won't make a jot of difference..

Brand PC?
Reinstalling OS from recovery disc won't remove shovelware.
(also with bridging internet connection PC can get infected before installation is complete)

Yeah that one was, but the recovery CD was quite rare and was literally just the OS, so no bloatware, although that wouldn't have explained why that PC as well was fine for years but then suddenly got the 100% CPU usage. Networking wise, it may have been connected to the router at the time but network drivers had to be installed by hand before the hardware would be recognised, but that's a possibility. This PC and my sisters PC are also hundreds of miles away from each other atm so it's doubtful if there was a virus it would be transferred.

Just a thought, could there be an issue with the MB/chipset, whereby it maybe gets stuck sending millions of requests to the CPU, overpowering it and explaining why there isn't a process visible in the task manager (as no actual process)? I don't have much knowledge of interactions between chipset/cpu etc though and where the task manager gets it's CPU usage figures from.

EDIT: or a ******* graphics driver? Although I guess thatwouldn't show the same symptoms and she would be complaining about stuttering.

 

[EsaT]

I don't know how many processes are open (probably about the usual 50-60 of vista, but i'll check next time I speak to her) but I got her to tell me the combined total of cpu usage of the visible processes, whch was about 10% (so the usual). That's the bit that completly stumps me, it would appear there is something cpu intensive using the processor (from the task manager stating 100% usage and problems with anything remotely intensive)

Vista is one huge bloatware and it seems to be very hard to find out what is eating what resources.
Lack of internet connection should mean that at least soem update shouldn't have broken anything... but then something might have crapped out all by itself like was common in 95-based OSes.

Graphs of this monitoring program show better if some process is periodically eating lot of CPU time:
http://technet.microsoft.com/en-us/sysinternals/bb896653.aspx

Just a thought, could there be an issue with the MB/chipset, whereby it maybe gets stuck sending millions of requests to the CPU

Hardware level functions aren really complex, complex stuff is done under control of software.

 

[Amp34]

Vista is one huge bloatware and it seems to be very hard to find out what is eating what resources.
Lack of internet connection should mean that at least soem update shouldn't have broken anything... but then something might have crapped out all by itself like was common in 95-based OSes.

I would disagree with your first comment tbh but each to their own. The other PC runs XP so it's not necessarily anything specific to do with vista (if of course the cause is the same). I think unless someone else has any other ideas it will be a case of waiting and see if it is a problem with the OS, but easter is a long way away which is going to be a pain for my sister, and I still have a nagging feeling reinstalling won't make a blind jot of difference.

Thanks for the link, i'll get her to try it out and see if that comes up with anything different.

 

[relax]

Firstly, make the effort to install realvnc or the likes if distance is an issue - suicide is a better choice than trying to sort this over the phone but talking someone through install realvnc is fairly easy (click next click next type in password blah blah).

You can rule out a lot of software and driver issues by just booting into safe mode.

Do a "microsoft update" rather than "windows update" Google process explorer + rootkit revealer (they should be hosted on microsoft.com) and check to see if any thing is shady.

If you built both of these computers, and you used a "shady" copy of windows then the chances are its rootkitted before you finish installing windows.

In the past i have had NIC drivers which would freak out locking the box up 100% cpu usage when downloading over a few mbit (this wouldnt show up in taskmanager), and more recently on my laptop graphics driver that would freak out and go to 100% cpu when doing simple things (this one did show up in task manager).

 

[Amp34]

Thanks relax.

I was wondering about remote desktop software, i'll see about getting that sorted, good idea on the safe mode too, if it is the NIC then it should show up when booting between safe mode and safe mode with networking I assume?

Both copies of MS are legit so that rules that out, and i'll look for that rootkit revealer too.

 

[Mattus]

What I would do to narrow down the problem is to open task manager and go to the performance tab, then select 'show kernel times' from the view menu (I'm on XP right now, wording might be different on Vista, but the option does exist.) After you've done that, the amount of CPU which is being used for OS-level functions as opposed to programs will show up red on the graph. If most of the CPU usage is red then it generally points to a driver or OS-level issue rather than a program that's been installed on the machine.