CPU useage 100% problem on 2 Laptops

[Steve Bird]

We recently had an infected PC connected to our office network. One laptop
running Norton AV with upto date defs threw up a warning of Bugbear.m and
cleaned a file. Since then the PC is running very slow and the CPU usage
indicates 100% nearly all the time. SVCHOST seems to be using about 70% and
System using 30% with very little running. If the PC is rebooted it seems OK for
a while but after using the internet (IE5.5) it goes to 100% again. The system
has been scanned many times for viruses but none have been found!
Any ideas? The OS is W2K SP2.
Sounds like a virus but can't seem to find anything even when I search for the
..dll and .dat files associated with the Bugbear virus

We have another laptop (the culprit) running same OS but unable to load any AV
is it crashes out. Using an online AV checker some viruses were found and
removed. I tried looking through registry using regedit but the window closes by
itself after about 5 seconds!
Any ideas?
Also sounds like a virus of some sort but not getting anywhere fast!!

Thanks
Steve

 

[Vanguard]

We recently had an infected PC connected to our office network. One
laptop running Norton AV with upto date defs threw up a warning of
Bugbear.m and cleaned a file. Since then the PC is running very slow
and the CPU usage indicates 100% nearly all the time. SVCHOST seems
to be using about 70% and System using 30% with very little running.
If the PC is rebooted it seems OK for a while but after using the
internet (IE5.5) it goes to 100% again. The system has been scanned
many times for viruses but none have been found!
Any ideas? The OS is W2K SP2.
Sounds like a virus but can't seem to find anything even when I
search for the .dll and .dat files associated with the Bugbear virus

We have another laptop (the culprit) running same OS but unable to
load any AV is it crashes out. Using an online AV checker some
viruses were found and removed. I tried looking through registry
using regedit but the window closes by itself after about 5 seconds!
Any ideas?
Also sounds like a virus of some sort but not getting anywhere fast!!

Thanks
Steve

svchost is the manager for the NT services. Try going into the Services
applet and stopping each non-critical service to see if CPU usage drops
when a particular one causing the usage gets stopped.

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[Steve Bird]

Thanks for the info. I did look at this solution previously but didn't know what
could be stopped and what couldn't.
How do I know which is a non-critical service?

Steve

 

[Vanguard]

Thanks for the info. I did look at this solution previously but
didn't know what could be stopped and what couldn't.
How do I know which is a non-critical service?

Steve

I don't have a list and don't right now have a link to one as to which
are critical and which are not. A critical service usually cannot be
stopped. However, a non-critcal service getting stopped can reduce
functionality but then the point is to check which one when stopped
reduces CPU usage and not that you can continue using the system (i.e.,
you may have to reboot). So just try stopping each one and watch the
CPU usage in Task Manager. If you stop one that hangs the system or
makes it unusable, well, then hit Ctrl-Alt-Del and logoff or restart
Windows and continue trying the rest. The goal is to determine which NT
service is banging the CPU usage, not to retain a stable system
thereafter.

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