Inspiron N5050. There is no power light on. The end of the adapter reads 19.94v at the inner wall and 2.4v at the center pin. With the 7 pin connector disconnected from the mobo I get 19.94v at all 3 reds and 2.4 at the blue. When I plug the connector into the mobo and check at the pins soldered to the mobo I get 19.94 at all 3 red and .35 at the center(blue). Is this how it should be or is there a problem somewhere? I had this problem about 2 months ago and just set it aside. When I finally got back to it today It had the pwr light and started up. Ran it for an hour and shut it down. Came back 2 hours later and no pwr again.
First thing is to try/change out the power supply..This could be a number of things, you will just have to narrow them down.
Have you tried another Power Supply ? If the computer Will not Turn on, it is often the Power Supply or Ram or Motherboard.. Also check the power cord for cracks..