hi all, My laptop wont start, when i press the power on switch the lights go on and the fan spins for about 3 seconds then the fan stops and lights stay on, i troubleshooted a few different things such as changed the ram, hard drive and tried it with/without battery/adaptor, The adaptor was charging the battery and the battery was holding its charge when being powered on its own Whilst trying to solve the cause and ruling out possible problems i managed to get it to work ok by just temporaly disconnecting the fan, obviously i only did this breifly but long enough to give me a display and to see that it worked fine, so i turned it off and re-connected the battery, tried again, and still worked fine, Then when putting it all back together like the cases etc i noticed that the black cable that connects to the wifi card was damaged and not connected and subsequently possibly grounding on the body, and so i assumed this was the problem as it wasnt touching the body when i got it to work, So i replaced the cable and connected as should be done, not until about half way thru this task did it occur to me that this cable is only a signal and nevertheless unneccesary and not the cause of my problem, lol, silly mistake, i know. However this brings me to it current status after putting it all back together it has also put me back to square 1 again and i cant get it to start again, and is the same as it was when it first went wrong, Can any1 help??????? Sorry about long post and i hope its detailed enough and i havent missed anything out, All help and suggestions are much apprieciated, thanks Shaun

Is the fan turning freely? Is the inside of the laptop dusty? What about the air inlet vents?