I recently purchase an old MacBook Pro from a friend for a small price, it was in perfect condition and barely used. After about a month, the GPU went crazy and I got the classic pixel screens and such. After many tests at a local Mac repair shop we determined it was most likely the common issue with that models particular graphic card and that a "bake" of the board (since the card is soldered directly to it) was the most realistic approach, as I was not about to invest in an old MacBooks repairs any further. I opted for the heat gun as opposed to the oven technique. I properly covered the other components in a heat shield leaving only the GPU exposed. I went over the piece for 5-7 minutes on a relatively low heat, let it cool for a while, then began to reinstall the board and all other connections. I got some brand new Arctic Silver for the chip and the others on the board, after cleaning it correctly with isopropyl alcohol. As far as I know this all worked, but now I have a new issue... The macbook won't start at all anymore! Prior to this is would get at least to the apple screen but be pixelated and freeze up, and in safe mode could get to desktop but it was near impossible to see what you were doing. BUT NOW it won't boot at all. The only sign of life I can find is a faint high pitched noise from the HDD - from a distance sounds like a constant beeping, but up close I notice it's more like the sound of the arm or disk attempting to move. I took all normal procedures and resetting of pram and all the usual stuff. Only time I get any change in the situation, is if I hold the power button for about 7-10 seconds, remove the power (it has no battery, so this cuts off all power) while still holding, wait 5 or so seconds, plug it back in, release the power button once I see the green light on the power adapter I active, and instantly both fans speed up to max speed, screaming and do not stop until I remove all power again. I have a lot of important stuff on this drive and no means to access it otherwise, and my iPhone is synced to it which means I can't do anything new to my iPhone without wiping that since it can only sync to one computer at a time.