2 Updates:

1) The power button will in fact do at least two things, flash orange or being lit steady orange.

2) I would recommend, with all plastics (wires, etc) moved out of the way, to hold the heat gun on longer. You will not hurt the board and I think you will get a better reflow. I held the gun on the board for approximately 2 minutes and had no signs of any sort of damage and the repair seems to be holding better.

Brief description of the problem: When you press the power button you get an orange light, hear the hard drive spin up, and hear the CPU fan turn on. But nothing else. Other than the lack of activity and orange light, there's no sign that there is a problem, no video at all, including backlight.

As described in the video I used a heat gun (hair dryer WILL NOT work because it doesn't get nearly hot enough) to heat the entire main board (motherboard) slowly and methodically. When I put it back together, it worked for several months with no problems. But ... it inevitably failed again. While doing the initial repair I made a mental note of the lack of good thermal grease between the heat sink and cpu/gpu. Where there was a fair amount of paste (on the CPU) it was dried out and had lost all liquid/paste properties. Unfortunately, I didn't take the time to act on that mental note and I just put it back together and went about my business. The second time it failed I did the same thing, but this time the repair 'worked' for less time.

The third time (a few days before the making of this video) I decided to try baking it. I was more concerned/side-tracked with melting the solder all over the board than focusing in on the actual cause of the failure. I believe the failure was actually caused because a few months before the initial failure I had changed the computer settings to allow the computer to stay in a rest mode with the screen saver on for an extended period. I think that swirly line screen saver caused the gpu to get too hot. So ... this time it kind of had a little eureka moment where I decided to diagnose the failure more accurately and ONLY heat the gpu. It worked. So heating the entire board was not necessary because the cause was 1) lack of quality thermal grease on cpu/gpu which led to 2) cold solder joints that needed to be reflowed.

So to wrap this up, take the back of the computer off (2 screws), then the bottom stand (3 screws I believe), then the two covers over the mother board. Technically, I think you can leave the smaller cover attached to the larger cover. I think there are 4 screws holding the larger metal cover. Next remove the heat sink. There are 3 or 4 screws holding it down on the motherboard and then 3 I believe holding the fan down (when you lift the fan up at the foil tape line, you'll see another screw). remove any cables in the vicinity of the gpu and use the heat gun to heat the gpu. I held it for probably 10 seconds and then pulled it off. CAUTION: the heat gun gets extremely hot, I'd recommend cycling on and off the GPU in no greater than 10 second stints in order to prevent damage to the board and components. When you're done, turn it back on to test. Do NOT leave it running with the heat sink off! If successful, immediately turn the computer back off and put everything back together. But ... use thermal grease this time. Make sure you clean the old grease off. It scrapes/wipes off really easy. And I'd recommend removing the cpu from the board to wipe it off. No need to get all that old crusty paste on/in the motherboard.

Thanks for watching and let me know if you have any questions.

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