PC Games randomly slow down then speed back up

[GhsCrysis]

So I've had this computer for about four or maybe five years now, and it worked fine up until about 7 months ago. Then I started having this problem where any time I ran any game (Heroes of Newerth, World of Warcraft, Call of Duty, etc.) it would run fine for maybe three to five minutes, then it would slow way down for maybe two or three minutes, then resume normal pace for three to five minutes, repeat.

I couldn't ever find a fix, so I just stopped using my desktop all together and swapped to my laptop for about four months, then decided to try my pc again, and for some unknown reason it worked. Then two days ago it started doing the same thing as before with all games, slowing way down then going back to normal.

So far I've tried restarting it, obviously, I opened it up and used some compressed air to clean it out and see if that had anything to do with it but that didn't work either. Everything I've read online said it was overheating, but when I ran ATITool it stayed at about 120-130 F, which isn't ideal but doesn't seem like it'd be enough to slow everything down.

I don't really know where to go from here, I feel like it's something that should be fixable, but I just don't know how, absolutely nothing changed between Saturday (When it worked completely fine) and Sunday (When it started running slow).

Does anyone have any type of suggestions for what to try? Any help is greatly appreciated, thank you.

 

[Thomas]

What are your specs? Cpu, board, vga? It's hard to help when we don't know what you have.

 

[GhsCrysis]

Yeah, prob woulda been smart to put that in the original post... heh.

CPU: Intel Core2 Quad CPU Q6600 @ 2.40GHz
VGA: NVidia GeForce 9400 GT
3GB RAM
Windows Vista

As for motherboard, I was running Everest Home Edition and it said the motherboard name was Unknown, so not too sure what to do to get that.

Thanks for the quick response.

 

[Slaymate]

I would start by monitoring your temperatures for an hour or two, cpu and gpu. If either the cpu or the gpu get to hot they will throttle themselves down in speed in an attempt to cool themselves down.

 

[curtis ensley]

Ya he's right it sounds like a heat issue mostly

 

[Apokalipse]

Overheating CPU is one possibility.

With 3GB RAM and Vista, it might be running out of RAM and paging data in and out of page file. So I'd check how much RAM is being used while you game too.