Need help with odd slow-mo problem o.O

[KingBob]

I'm having a very strange problem (or 2) with my comp that need help with. Every once in a while, it goes into super-slow-mo-mode, where every graphic gets slowed down a bunch. It's not lag, it runs very smooth, and at a high frame rate (WoW starts running at 80fps with 76 ms lat, but sloooow), just slow and steady.
Nothing but the graphics seem to get slowed down, for example, if I cast a spell in WoW, the bar starts, gets half way through, and casts the spell at the right time.
Audio doesn't slow down, just video. But flash audio gets crackly.
The problem only happens every once in a while (it gets more frequent though), and only while certain programs are running. So far, these programs are Windows Media Player, iTunes, an internet page using flash (like youtube, or banner ads), and Wc3 WE. However, it affects everything, from 3ds max playback speed to the little effect Windows makes when you minimize something. (Also, as a side note, youtube videos play at a normal rate, but the sound is crackly).
The problem goes away sometimes if I'm streaming media over the internet... via YouTube or a radio station running through iTunes. When it stops, any audio coming out of my speakers d-d-d-d-d-d-d-d-d-d-does that annoying skippy thing that audio sometimes does, and everything is back to normal.
It never happens twice between reboots.
Does not boost processor usage at all.

Can't think of any more information on that problem... so, now for the next one...

The second glitch is just as sporadic as the first. It puts the computer into "periodic freeze" mode, where every 10 seconds it freezes for 5 seconds until I reset.
This glitch effects Everything, including the mouse.
Usually only happens sometime after the first glitch stops.
Not much more to say on this one, other then its annoying as hell.

As for system uses, I use it for gaming, animation, programming, and watching/listening to videos/music.

As for system specs:
OS: Microsoft Windows XP Home Edition (SP2)
Motherboard: ASUS P5K SE
Processor: Intel Core 2 Quad Q6600
Video Card: Nvidia GeForce 9600 GT
Ram: 2048 MB DDR2-SDRAM
HD space: 1320 GB (only 129gb used)
Chipset: Intel P31/P35
Audio device: 8201IB/IR/IH(ICH9 Family) HD Audio Controller
Audio software: Realtek
AntiVirus: AVG

Bought it about 2-3 months ago, so its definately not because it's old.

I took it in to the computer store 3 times to get it fixed. The first time we did a graphics card swap: didn't work. Second time we tried updating the BIOS and some other drivers: didn't work. Don't remember what happened the 3rd time 0.o
I haven't told them about the second thing yet though
At least it's under warranty, so anything I bring it in for regarding this issue is free ^_^

Can't think of anything else to say. Any help/suggestion would be greatly appreciated.

 

[FF7 project-G]

well i know this is kinda late and everything but right now im guessing it might be because your video card might be overheating. Could you provide specifics like fans voltage and such?
EDIT- especially the SDRAM, it has alot of tendancy to overheat because of the voltage it uses, the good part about sdram is that it works faster.

 

[FreshMobster]

Isn't the warranty automatically cancelled when you open your case (as in not by special personnel)?
Anyways. Probably the issue could be dust or even small particles of animal hair stuck up in your comp. Try opening it and dust it out using compressed air (don't try using vacuum cleaner, as most of them produce electrostatic discharge running through the pipe, which can easily kill some of more vital computer components). Don't forget to take off CPU fan and t clean heatsink using a piece of tissue. It's also advisable to take off the old CPU thermal paste and apply a new batch of it (Arctic Silver is the all time legend, and best for home users). Who knows what kind of crap may be there. Most of computer-building companies don't really put good stuff there. Also apply a patch of thermal paste on top of your graphics card memory and GPU.
If this doesn't help, try defragmenting your Hard Drive. Forget about the one bundled with Windows - it cannot process large files and is slow. Better solution would be installing O&O Defrag and performing defragmentation process with it. To defragment some core system files (hibernation file, page file), that are locked by default while Windows is turned on, you can use System File Defragmenter program (it's free and found at Microsoft site for download).
Oh, and try increasing Page File size.