First thought, since you said you've had the system for "a couple of years" is when is the last time you blew out the fans and exhaust ports?
I have been having some issues with my notebook as of late. When playing a hardware intensive game, everything will be fine for 10-15 minutes, and then the FPS will drop to around 5-15fps for a few minutes. After a few minutes of that, everything will return to normal. I have had this laptop for a couple of years, and it is built to play games. I have never had these issues in the past.
I changed my video drivers a couple of times to no avail. I am using modded .inf drivers.
Today, I started up Far Cry 2 with Speedfan running, and when the game slowed down, I alt+tabbed out to check Speedfan, and found that each of my CPUs were running at over 65c, with Core0 pushing 70c. Speedfan isn't giving me any information on my GPU, but I bet that it isn't very cool. I did not have Speedfan regulating fan speed. I had them set to maximum.
Since I'm not getting artifacting, I don't think that there is any damage to any hardware components yet. I believe the sudden FPS drop is from my CPUs scaling back their clock when they hit a certain temperature. What concerns me is that this is a new problem, and one that I've only seen for the last few weeks. The fans are clean, the notebook sits on my desk all of the time and has a decent berth to allow airflow. The room is not usually warmer than 21-24c. The notebook has little legs so it is sitting up off the desk. Any ideas?
Thank you for your time.
Operating System: Windows XP Professional (5.1, Build 2600) Service Pack 3 (2600.xpsp.080413-2111)
Language: English (Regional Setting: English)
System Manufacturer: CLEVO
System Model: D900C
BIOS: BIOS Revision: D900C 1.00.03E2
Processor: Intel(R) Core(TM)2 Quad CPU Q6600 @ 2.40GHz (4 CPUs)
Memory: 2046MB RAM
Page File: 658MB used, 3280MB available
Windows Dir: C:\WINDOWS
DirectX Version: DirectX 9.0c (4.09.0000.0904)
Card name: NVIDIA GeForce Go 7950 GTX
Chip type: GeForce Go 7950 GTX
DAC type: Integrated RAMDAC