CPU Usage out of control

[SQL_n00b]

Lately my computer has been getting slower by the day. Attached are images of the 'Processes' tab in the task mgr.
Image 1: List of processes sorted by CPU
Image 2: List sorted by Memory Usage

If you look at image 1, the System Idle Process CPU Usage = 92%. However, right at the bottom of the Task Mgr, you see CPU Usage to be 51%. Sometimes it goes up to 75% too. Don't quite understand the discrepancy.
I always thought that 100% - System Idle Process% = CPU Usage%. Is my assumption wrong?

Or is there some kind of unlisted process running in the background - like a virus or so? If yes, how do I detect it/them? Doing a malware/spyware/virus check using Avast, Super-antispyware, Malwarebytes hasn't found anything yet.

The other thing that I can think of is that it could be because my hard drive is running low - have only 1.5GB of 59GB left. which brings me to my next issue. The C:\Windows\Installer folder is taking up 23.2GB. WTH?!!!

Anyone know what's screwing things on my machine?

Sys Details:
Win XP Home - SP3
1.5GB RAM
C Drive: Used: 1.59 of 55.4GB
D Drive: Used: 8.94 of 19.0GB

Thanks!

[donkey_pasta]

I have read before that bad RAM can cause inaccurate readings -- you can test your RAM using Memtest86.

Also, you could try an alternative Task Manager like Process Explorer and see if it yields the same results.

[SQL_n00b]

I have read before that bad RAM can cause inaccurate readings -- you can test your RAM using Memtest86.

Also, you could try an alternative Task Manager like Process Explorer and see if it yields the same results.

I have downloaded Process Explorer (PE) to explore the processes in more detail and all I can see is that Java Quick Start (listed as jqs.exe in PE) is one of the major culprits - it seems to suck high amounts of CPU intermittently, and that is usually followed by high CPU usage by something listed as Hardware Interrupts. What's causing these Hardware Interrupts and how do I get rid of them?

[donkey_pasta]

Try uninstalling Java Runtime Environment, reboot, and see if it still has high CPU issues. That will tell us if it's directly related to Java or not.

[SQL_n00b]

Try uninstalling Java Runtime Environment, reboot, and see if it still has high CPU issues. That will tell us if it's directly related to Java or not.

In the Java Control Panel, I unchecked the box named 'Java Quick Starter' to see if that fixes things without actually uninstalling JRE. What I now notice in Process Explorer is that Hardware Interrupts constantly account for anything between 5%-50% of CPU Usage.

I have read somewhere that if the Current Transfer Mode of the Primary IDE Channel is set to PIO (Programmed Input/Output), then that might explain the constant Hardware Interrupts. The default transfer mode was chosen to be 'DMA if available', but something went amiss that seems to have switched it from DMA to PIO. Anyone know how to deal with this? And if messing with the registry to switch back to DMA is going to cause any other side-effects??

[gerbil]

I think you have a case of Installer bloat there. My Installer folder is just 125MB.
There is a M$ tool to show up orphaned Installer files [those not registered] for you to delete; perhaps you could give it a try?
http://support.microsoft.com/default.aspx?scid=kb;en-us;290301
Run :
msizap.exe G
"And if messing with the registry to switch back to DMA"... try the BIOS selection first. And you do not need to directly edit your registry - use Device Manager to set your IDE drives to DMA if available. Look under IDE ATA controllersproperties.
A site for you: http://winhlp.com/node/10
What was using java?

[SQL_n00b]

I think you have a case of Installer bloat there. My Installer folder is just 125MB.
There is a M$ tool to show up orphaned Installer files [those not registered] for you to delete; perhaps you could give it a try?
http://support.microsoft.com/default.aspx?scid=kb;en-us;290301
Run :
msizap.exe G
"And if messing with the registry to switch back to DMA"... try the BIOS selection first. And you do not need to directly edit your registry - use Device Manager to set your IDE drives to DMA if available. Look under IDE ATA controllersproperties.
A site for you: http://winhlp.com/node/10
What was using java?

Tried msizap.exe, but didn't really do much good. Of course, I wasn't expecting the tool to just free up more than 20GB of space. In fact, it hardly made any free space.

So I ended up cutting the folder off of my laptop and stuck into an external drive. However, doing this may create problems for me later when an app needs to run an update/patch for an existing installation. If anyone know another way to deal with this, I would really like to know.

As for the Primary IDE channel thing, http://winhlp.com/node/10 was the best and easiest of all solutions I came across. Thanks for that, gerbil!

[SQL_n00b]

Tried msizap.exe, but didn't really do much good. Of course, I wasn't expecting the tool to just free up more than 20GB of space. In fact, it hardly made any free space.

Well, I should take that back! I didn't use the zapper utility quite the way it is supposed to. I was just running (double-clicking) the MsiZap.exe executable which was why it wouldn't do anything.

Ran it the proper way today and that cleared about 22GB of space off of my C: drive in less than 3 seconds.

For those of you who are interested, here's a helpful URL to a blogpost:
How to remove orphaned Windows Installer files

[gerbil]

:). Yeah. Always read the instructions. Sometimes, just sometimes where I am concerned, they are good to follow.
But in this case out of habit I put in a "/" before the parameter g. Wrong.
A procedure: download the file msicuu2.exe from http://support.microsoft.com/default.aspx?scid=kb;en-us;290301
Dclick it to install the cleanup application. Go to that Windows Installer Clean Up folder in Program Files and drag a copy of MsiZap.exe to your C: root.
Open a cmd window, and enter:
cd \
msizap g
And bang! it is done.
Remove msiexec.exe and perhaps uninstall the application.