Hi!

I replaced my DC-in board and by following a fixit.com guide. It went pretty smoothly, and when I started up the laptop, the fan came on very loudly initially, then turned off. After about 45 minutes, the fan cam on again (much louder than normal) and then the screen went black. Hitting any key turned it on again but the same thing happened.

My first thought was the fan was obstructed when I reassembled it, and the excess heat is shutting down the machine. I've reassembled it, but the fan spins freely and I don't see any obstructions.

The only things I can think of are these:
-- The routing of the wiring may not be exactly as it was, and that little bit makes a difference, or
--The two large screws with springs that hold the heat sink in place do not seem anchored to the motherboard, but it looks like it was like that before I got to it.

Could either of those be causing the problem, or is it something else? Before the repair the fan was quiet.

Any input helps.
Thanks,
Elizabeth

Those screws in the heatsink sometimes break off from the bottom case and will just cause the screws to spin and not apply much pressure to the chips. You may want to take the heatsink back off, make sure the screw holes are still attached. You may also want to make sure nothing is in between the heatsink and the chips except for a good even coat of thermal paste. If the thermal paste looks old, you may want to clean it off and apply a new coat.