Why does my computer lag randomly?

[exspeednfs]

So I have this computer which lags. It starts lagging after a while after I switch on my computer. I play Battlefield 3 and Call of Duty 4. The problem is that the framerate gets really choppy and it drives me crazy, especially when I am about to takedown someone. So i rage-quitted and found out that Windows is lagging too. A usual web page takes less than 10 seconds to load, but with the lag it takes about a minute. Closing programs also takes longer and sometimes it freezes for a while. I figured that it might be caused by overheating but I checked the temperature with EVGA Precision X and the temperature is only about 40-50 degrees Celsius. Here are my specs:

Intel i3-530 2.93Ghz
Nvidia GeForce GT 610 2GB DDR3
4GB DDR3 RAM
Gigabyte GA-H55M-S2

 

[correon]

Try download Core Temp - it checks direct inside the core - you should check your GFX temp allso - there is some gadgets you can get to check your GFX .
Check your air inlets and outlets that they aren´t blocked with dust
Check if some drivers need updating

 

[exspeednfs]

I downloaded the latest driver for my GT 610 but when I tried to update it, an error message saying '%1 is not a valid Win32 application' appears. I downloaded Core Temp too and temperature remains at 48 degrees Celsius max.

 

[exspeednfs]

OK found out that after running Battlefield 3 the max temperature went up to 66 degrees Celsius.

 

[correon]

Check if your Gfx is getting hot allso - you can download a gadget called GPU Meter.

You should check that your computer is Spyware free - maybe run a defrag if long

time ago and a discclean.

 

[exspeednfs]

Well EVGA Precision also shows about 50 degrees Celsius for my GT 610. I used CCleaner and fixed all registry errors and cleaned up my system- removing temporary files etc. The lag seemed to have reduced and my computer functioned quicker, but the lag returns again after a period of time.

 

[exspeednfs]

I also encountered another problem. While playing Battlefield 3 the monitor suddenly shows no input, but the computer remains switched on and running normally. The monitor becomes idle. I checked my graphics card( I took off the CPU case) and found out that the fan of the graphics card has stopped spinning.