Sounds like time to clean out temporary files and defragment the system. 
I use a tool called CCleaner to handle the cleaning chore, and the 
standard Disk Defragmenter program in the System Tools folder of the 
Start Menu takes care of the other. Fragmentation happens over time as 
you use your system, and the temporary files a program makes to cache 
data get left behind when the program closes instead of being deleted 
properly. CCleaner finds and gets rid of temporary files, browser cache, 
and other stuff, and Disk Defragmenter stacks the remaining systems on 
your hard disk nice, neat, and easy to use. I use both programs on my 
own machine every week, but other users may find that every two weeks is 
sufficient. Experiment a bit and find what works best for your usage. 
Hope this helps some. :)

P.S.: Your initial idea to reboot is a good first step. It is my first 
rule of Windows computing: If in doubt, reboot. :)

Missy Hoppe wrote:
> Hello. I'm having a really weird problem with my new computer system and 
> hoping that someone on this list might be able to help me find a way to fix 
> it.
> First of all, here are my system specifications.
> Abit AB9 QuadGT motherboard with bios 13, Intel qx6700 processor, Zalman 
> 600W power supply, 4 GB
> kingston hyper-x 8500 memory, Zalman 9700 cpu cooler, 4 80 mm
> thermaltake thunderblade fans, 1 120 mm thermaltake thunderblade fan,
> MSI 8500 video card, Windows XP Media Center edition sp2, 2 sata Samsung
> dvd ram drives, Creative x-fi extreme music sound card, Samsung 500GB
> sata hard drive, Samsung 17 inch LCD monitor and Apevia x-Dreamer2 blue
> case.
> I'm using a screen reading program called Jaws for Windows, but I'm
> almost certain that this problem is happening with or without my screen
> reader running.
> I am using the windows classic theme with standard colors, and as far as
> I know, have made all necessary video changes to adjust for best
> performance, unless there's more changes I need to make from within the
> nvidia control panel, which I can't seem to access very well with my
> screen reader. I'm running at 1024-768 resolution in 32 bit color mode. In 
> general, the only programs that are running constantly are AVG Free edition 
> antivirus software, Windows Defender, Outlook express and my screen reader.
> This new system has been up and running for about 3 weeks, and  on the
> whole, it has been simply a joy to use; it hasn't ever locked up on me,
> and I've been amazed by how many things I can accomplish simultaneously.
> Unfortunately, I am experiencing an extremely weird problem that I'm
> hoping someone on this list might be able to help me resolve.
> After running for a couple of hours, my system becomes very sluggish
> when performing certain tasks, most noteable of which is attempting to
> enter the control panel. The slowdown is also very noticeable when
> minimizing all applications and going to the desktop and also wen
> working within any other dialogue boxes.
> I've tried checking things out in task manager, and everything appears
> to be just fine; nothing appears to be significantly bogging down the
> system. If I reboot, everything goes back to working instantaneously for
> a couple of hours, and then the slowdown returns.
> Does anyone have any ideas for things I might try to resolve this issue?
> Are there any bios settings I might be able to change that could have an
> effect in this situation? I've written to the Abit forum, and they 
> suggested disabling eisd and C1E from withing Bios, and as soon as I have 
> someone with vision around here that I can trust to go playing around in 
> Bios, I intend to investigate those options. In the mean time, though, I'd 
> really appreciate any other advice that you may have.
> I haven't attempted any overclocking yet, but am eventually hoping to
> get the processor running at an even 3.0 GHZ. My system temperature
> rarely exceeds 90 degrees F, so I don't think it's an over-heating
> issue. I've tried disabling all non-essencial services in windows, and
> except for IE7, I have fully updated my system with all security and
> other patches.
> Any ideas you may have for things I can try to resolve this issue would
> be extremely appreciated.
> Thanks in advance for any ideas you may have, and I hope that you're
> having a really great day!
> Missy 
>
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