When I start a game, initially it runs smoothly, but after a couple of minutes, the performance gradually decreases to the point of being unplayable (1-2 FPS). The sound also starts to lag at this point.
This does not happen every time I start my PC, usually exiting the game, rebooting, then starting the game again solves the problem, and I can play with perfect FPS for as long as I want. I could not find any deterministic reason when this happens and when doesn't. It happens in every game I tried (SWTOR, Diablo 3, Skyrim), and not even games, but simple applications like a browser or the Control Panel can get unusably slow. This is a brand new PC I bought three months ago, and this problem occurs since the first day I've been using it.
Could you provide any advice how to further diagnose the problem? I tried to reinstall Windows, and tried different video card drivers, but it did not help. It would be important to know whether this is a hardware or software problem, because I can use the warranty if it is a hardware issue. (I did not want to return the PC yet, because I can't reproduce the issue deterministically.)
Spec of the pc:
- Motherboard: ASROCK H61M-HVS
- CPU: INTEL Core i3-2120 3.30GHz 1155 BOX
- Memory: KINGMAX 4096MB DDR3 1333MHz KIT
- Video card: GIGABYTE GV-R685OC-1GD HD6850 1GB GDDR5 PCIE
- HDD: SEAGATE 500GB Barracuda 7200rpm 16MB SATA3 ST500DM002
I am using Windows 7 64 bit.
Thanks a lot in advance!
UPDATE: I checked the CPU temperature with Core Temp, and it was about 50 °C.
However, today I started my PC, and started a game, and the FPS slowed down after a couple of minutes, so I checked the temperature again, and it was 102 °C, I guess that's extremely high. So I rebooted, then the temp slowly decreased to around 50 °C, then I started the game again, and played without any problem for an hour, and the temperature was still 50 °C.
Do you have any idea what can cause this symptom? Maybe the CPU fan does not start when I start the PC for the first time but starts after a reboot?