I was trying to watch a movie on my original MacBook Air but the video kept freezing and I had to keep restarting my machine. After a little bit of looking, I discovered that it was more than likely the TIM paste on the CPU and GPU.
The repair wen't really great! It took me no time at all getting into the inside of the laptop, un-screwed all the screws, pulled up the heatsink and I was beyond shocked at how much TIM paste there was! Oh my gosh!! It took me a while to remove it all, and quite a few Q-tips as well. I finally got the stuff off, shined up the CPU and GPU and applied the new Arctic Silver 5 paste as according to the instructions on ifixit. WOW!!! That made such an improvement! I was able to watch the same movie again without it freezing. Now if only they could throw two fans in the MacBook Air...
Take your time! Put down a white piece of paper to put your screws on and place them in a little diagram of how they came out. Use the right size bit too! Kind of stripped a few screws.. oops.