LapTop won't boot up- please help
Let me begin by stating I am a novice computer person.
I have a laptop (Prostar) from 2001. The computer has done very well but started showing some signs of problems a little over a year ago. What would happen is when attempting to power on, the harddrive lite would come on and start flashing and not boot up. Intially I could coax the computer to come on by holding the power button for 10 seconds or so, powering it off, and then trying to turn it on again. This process worked for a period of time but eventually it kept taking longer and longer to try to get it to boot. I would know if it was going to boot upon pushing the power button bc the hard drive lite would stay on and the screen would flash a couple seconds later and boot up. But, eventually the hard drive would come on (not flash) and the screen power lite would start flashing and the computer won't boot. Eventually this led to the cmoputer not booting up at all. I should add the mother board is a Fosa 2700C. So from here I disected the computer and put it back together in hopes that the problem was a connection issue. It didn't work. Then I bought a new battery thinking I was under powering. No work. Then I purchased a motherboard--same thing happened...hard drive lite flashes and the computer doesn't boot up--no monitor start--no bios start--nothing. Most recently I changed the processor. No change in the symptoms. Now here is my question- this is starting to get really expensive-could it be the heat sink or motherboard fan? I pulled the heat sink fan and the bearings are shot (DFB450705M90T- 5 V .3 AM 2 wire). I tested the fan by applying 6V (2 AA batteries) the fan didn't work until I gave it a little push. Could this have been the problem all along? I have tested all parts bought and they work. Finally I should add, if I turned the computer on and got it to boot up I could keep it on forever. Hence, once it is on it stays on. Please help I am out of possible solutions except for putting up another 80 dollars for a new heat sink fan without a guarantee that it will work? Is there an automatic kill on the motherboard if the fan doesn't work?