Monitor light works but blank screen

[duval904yeah]

when i turn on the computer the light on the screen turns green but the screen doesnt change. how can i fix this? i opened the unit recently to clean it, before i did that the startup would run for about 30 seconds then just shut down. any help getting the monitor to work and getting the computer to boot up?

 

[johnb35]

If you opened it up and cleaned it out, most likely a loose connection somewhere. Looks like you had an overheating issue to begin with. Was it really dirty inside? Remove and reinsert the video card if you have a dedicated card. Remove and reinsert the memory as well.

 

[OvenMaster]

Check very closely for leaking and/or bulging electrolytic capacitors on your video card.
I had three out of five that were doing both and caused this very same problem.
Replacing the capacitors ($7 and an hour of my time with a soldering pencil) fixed the issue.