I have a Presario 2500 laptop,Pentium 4 2.66ghz,446 MB of Ram, Window XP,and a Radeon IGP 345M...this laptop keeps on overheating.... Everytime i play a game and leave the power connected it will overheat in about 20 min. and if i disconnect the laptop will lag a lot. If this is a fan problem can someone tell me how to see if the fan is working?im not much of a computer guy