I have Intel(R)Core(TM)2 CPU 4400, 2GHz, FSB 800MHz processor, Mother board- asus P5G41C-M LX, 2GB DDR2 RAM & 450W PSU. I am willing to install a ATI HD 6670 1GB DDR5 graphics card. Is there any chance of over heating of the graphics card?
No, that's quite a low powered card so temperature shouldn't be a problem. Besides temperature is dependent on the type of cooler on your card and your case and not the specs of your computer