When pressing the power switch, my computer successfully opens and fans works fine. I cleaned the interior parts filled with dust but no usual beep sound heard in startup. No display either. Then, after a few seconds (maybe like 5-10 sec), computer closes and starts again. This process happens again and again until I remove the power cord.
May be, there is a problem in my CMOS battery, processor, videocard or PSI. I don't want to assume so I can make a sure decision for my computer. I am a college student and have less knowledge with computers.