CPU

[ss_sumukh]

I have a Lenovo desktop. Whenever I switch it on the led switches on for 3 secs and switches off for 1 sec and then switches until I pull the plug. The monitor doesn't show any display. I removed the ram and cleaned out the dust but the problem still persisits.

 

[calmstateofmind]

It sounds like your laptop isn't making it past POST. POST is a power on self test that checks each hardware within your laptop before boot up actually starts. Have you dropped it at all? And does it make any beeping sounds?