Okay, so I've searched and searched, and I can't find a forum ANYWHERE that google can see with my particular problem. It's a strange one, so try to bear with me. I can only describe what happens as a computer brain shart.
First off, I have Windows 7 x86 Ultimate Edition. I'm running a Pentium D @ 3.4 GHz, and 3 GB of DDR2 800 on a Foxconn G9657ma-8ekrs2h motherboard. My video card is an ATI Mobility Radeon HD 3650, PCI-E 16x 1.0.
Now, if I'm just messing around on the desktop (using pandora widget, surfing the web, using Word, etc.) then the computer runs just fine, no problems at all... usually. This remains the case when I'm playing a full screen game and I alt-tabbed to my desktop to check something on the internet or change the song or whatever. A couple times the desktop has frozen for about 5 seconds, then come back for about 1 second, then frozen for 5 seconds, then come back... blah blah blah. This cycle usually ends in a blue screen (which I can't get an image of because I don't know how to MAKE the computer blue screen), UNLESS I alt-tab back to the game quick enough, and then it just goes through its regular error that I've described below.
When the computer BSoD's, it only shows that screen for about 2 seconds, then the computer restarts itself.
The BSoD is not the real issue here, because it has only happened a couple of times (and hasn't happened in at least 2 weeks). Usually the issue that I'm trying to resolve doesn't end in a blue screen. Usually the issue just goes through its error and then everything's fine for anywhere from 5-45 minutes before it happens again.
But now onto the real issue, which I believe is causing the blue screen anyway. When I'm playing a game... really ANY full screen game... at random times while playing the screen will freeze, then change to all one color, then the monitor will restart and the game will continue. The whole error usually lasts about 5-10 seconds. During this time, the music from my pandora widget doesn't change at all... it keeps playing without a hitch. Also, when this happens on Starcraft II, it seems that it gives other players that 'Waiting for player...' dialog, and after a minute of total time stuck in the frozen computer error, they are able to drop me from the game. This makes me think that it's not just a video card error, because if it was, the game would continue unabated while my screen froze, and it would just look like I stepped away from my computer for a few seconds and then came back.
It happens in WoW as well, but I never get DC'd because of it. Also, sometimes it will do its normal thing, where I'm running along, the screen freezes, monitor resets, and BAM, I'm right back where I was when the error started. However, sometimes I will be farther forward than I was when the freeze happened.
It also happens in Portal AND Portal 2, with graphics set to low, medium, and high. The graphics don't seem to make a difference for when this happens, another reason I don't think the problem is solely the video card. With Portal, sometimes the screen will do its normal freeze (during which time the sound from the game will loop about half a second of audio over and over and over until the game comes back), and sometimes it will just straight up crash to the desktop. No error message, nothing, just game then BAM, desktop.
By the way, it's not JUST in full screen that this happens. It will happen (albeit less often) in windowed mode as well.
Oddly enough, the problem NEVER happens in League of Legends. Don't know if that's useful information, but it's certainly noteworthy.
Every once in a while, if I alt-tab right before the computer was going to have a brain shart, then the error will continue on the desktop (as I described int he first part), ending in a blue screen.
Again, I think the problem is actually with the whole system somehow, and not just the video card, because of the fact that it shows up to others as lag.
Any help or advice of how to go about fixing this would be greatly appreciated. I would just upgrade the damn box (because this didn't happen on my old, more powerful build -- but it got stolen so I was forced to go with very inexpensive parts).
Also, I've included 2 images of HWMonitor (someone at another forum suggested it, then never returned to give me feedback on them). The first one is while the system was idle, and the second one is after playing a game for about 5 minutes.
Thanks, and I'll check back periodically today to see if anyone needs more information.
Oh yeah, and if I posted this in the wrong section, please let me know where I should post it.
Okay, this is over now.
Oh, something worth mentioning... yesterday I installed another gig of RAM (making the total 4 gigs) and a new hard drive, which I installed a fresh copy of windows on and reformatted the original drive. After getting everything updated and patched, the problem still persists. I was playing Splinter Cell Double Agent and Oblivion and both games (while running with very smooth fps) did the freeze at least 4 times each in the 10-15 minutes I was playing them (I wasn't playing them at the same time). I'm really confused as to what the problem could be, but I would really like to get your input on ideas of how to find out. Thanks guys!