Are you running two 2GB modules or four 1GB memory modules? Try removing the modules one at a time, and see if your system stabelizes... You most likely have one bad memory module

I am pretty sure it is 4 1 GB ones.

I have thoroughly cleaned the inside of the machine now with compressed air cans and was a bit shocked to discover a lot of dog hair and stuff that had gotten into my CPU heatsink fan. I removed all of it and sprayed down all the components very thoroughly. I have since removed the side panel of the case (that includes a very large 72mm fan) and have pulled the unit out from my desk to let it run with the side off while angling the 72mm fan to still blow into the unit.

I also sat down an industrial desk fan and have it blowing directly into the case on the floor right at the motherboard and video card, RAM, etc. And I took a larger industrial fan and have it blowing from across the room into the side of the unit as well. So far so good.....no lockups.

Ahh, an overheating issue! I have a front case filter that catches most of my 2 cats hair before it get into the case. Good luck, and hopefully the thorough cleaning will do the trick

Thanks! I'm not sure if this was the case or not....overheating, that is. However, so far so good. I will let you all know of my progress. The freezing is so random it just seems to happen at any time so I will just have to see how it goes.

This is still occurring and this is slowly driving me FREAKING insane. It just seems to happen randomly. I can sometimes go for long periods of time without it occurring and then when it does it freezes the entire machine and I have to reboot to get out of it.

And I have also noticed that when this occurs the first time it tends to keep happening in spurts for a bit. So in other words, it will happen once and then happen 2-3 more times during a night or so. I have no idea what is causing this but I am honestly starting to suspect a hardware issue now.

PLEASE HELP!

One thing you may want to check, wich resolved my problem with the computer freezing is the motherboard. Check and see if it is burnt at all. I know it sounds odd but i did the 8 step antivirus got a new powersupply new ram and a new processor before I found out the motherboard was the culprit. Do the tests that Tmagic suggested. I also use NOD32 and I think its really good. It is possible that it could freeze your computer because of a new update it got that is not working right. They have fixed that update though. The memtest86 that they suggested will rule out a ram problem.

I checked inside my BIOs last night and here was the results of what I saw:

CPU: 48° C/118° F
Board: 43° C/109° F
MCP: 57° C/135° F

CPU Core: 1.18v
CPU FSB: 1.20v
Memory: 1.86v

CPU Fan Speed: 2445 RPM
Aux Fan Speed: 0 RPM
NForce Fan Speed: 5283 RPM
Chassis Fan Speed: 0 RPM
Chassis Fan 2 Speed: 1454 RPM

I did find the following infection when I ran a scan earlier with Nod 32.

C:\Users\Jonathan\Desktop\System Tools\SmitfraudFix.exe Win32/Hoax.Renos.DWS application

Here are the results of my Malwarebytes' Anti-Malware scan (it found no threats).

Malwarebytes' Anti-Malware 1.40
Database version: 2723
Windows 6.0.6002 Service Pack 2

8/31/2009 11:14:43 PM
mbam-log-2009-08-31 (23-14-43).txt

Scan type: Full Scan (C:\|E:\|F:\|G:\|H:\|)
Objects scanned: 437866
Time elapsed: 1 hour(s), 30 minute(s), 8 second(s)

Memory Processes Infected: 0
Memory Modules Infected: 0
Registry Keys Infected: 0
Registry Values Infected: 0
Registry Data Items Infected: 0
Folders Infected: 0
Files Infected: 0

Memory Processes Infected:
(No malicious items detected)

Memory Modules Infected:
(No malicious items detected)

Registry Keys Infected:
(No malicious items detected)

Registry Values Infected:
(No malicious items detected)

Registry Data Items Infected:
(No malicious items detected)

Folders Infected:
(No malicious items detected)

Files Infected:
(No malicious items detected)

So is the computer still locking up?

As of yesterday......yes.

Like I said check to see if your mobo is burnt dude. Weird unexplainable shut downs like you are experiencing sounds like a hardware issue. Have you tried reinstalling your windows?
a burn on the mobo may only look like a darker colouration of a small part on your mobo. It may not be "black" but whatever colour your mobo is their could be a small little section where the colour has darkened. Check around your graphics card.

It is extremely rare that a motherboard shows any signs of burning or discoloration. It is much more common for capacitors around the CPU to bulge and leak brown or black stuff. This may be what Gordon9999 is talking about

Any other ideas? This is still occurring and driving me insane. I have tried just about everything I can think of!

A fresh format and reinstall of Windows? Is it in your future?

I downloaded Riva Tuner last night and ran it. I noticed my core temps were around 72-74 degrees when sitting at my desktop with the video game, Aion, minimized. When I brought the game up at the login screen the temps started steadily rising. When I was actually playing the game the temps went up to the mid 80s or so. I wonder if this could be the issue.

very possible. I hope it all works out for you dude.

Yes you need to open the computer case and monitor the temps and game freezing with it open