1 - 2 horas
I bought my 60 gig PS3 used, about four years ago. Since then I had to have power supply issues fixed twice, and the YLOD fixed once. I had watched a few YouTube videos on how to fix the YLOD, but was intimidated by all of the disassembly required. When I got the YLOD for a second time, I knew I wasn't going to spend the money on having it fixed again; and since I was essentially giving up on the PS3, I figured if I messed it up trying to fix it, it wouldn't be any more of a loss from what I already had. I searched through videos on how to fix it, including IFitIt's, and after fruitlessly searching my local Radio Shacks for thermal pads and paste, I ordered the reasonably priced IFitIt YLOD Fix Kit.
I took it slow. I had the repair walkthrough video set up on my desktop, and the instruction slideshow on my laptop, and started taking my PS3 apart. As PS3 innards started piling up around me, I began to worry about my ability to put it back again, but I kept finding all the little screws to remove and ribbons to release, until I had a bare motherboard in front of me. Cleaning the CPU and GPU were relatively easy. The hardest parts about heating the board was finding something in the house that was actually level, and keeping my curious kids away from it while it cooled. After some experimentation I managed to apply a nice, smooth layer of thermal paste, got my thermal pads in place, and by paging back through the instructions, had no problem putting the PS3 back together.
My family gathered around as I plugged the PS3 back in to the TV. We watched the blue light stay blue with mounting joy. There was a moment of worry when the PS3 told us that it hadn't shut down properly and needed to check for errors. But a minute later our log-in screen was up, and my kids were cheering. The repair had worked, the PS3 was alive!
And then we tried to put a disc in. The drive was not letting anything in.
I took the PS3 apart again, figured out how to open the blu-ray drive and get it aligned to accept discs, then noticed the stupid broken wire on the side of the drive. Whatever it does, it is apparently essential enough to render the entire drive useless. And, unfortunately, IFixIt, and the rest of the internet, had no parts and fix options for the PS3's blu-ray drive - and a used replacement would be $60-70 bucks, with no guarantee that it would work based on the customer comments. Thus my initial pride at having accomplished the repair devolved back into broken PS3 despair.
Watch out for that stupid little wire on the side of your blu-ray drive! And by small, it is seriously like 2-3 copper wires small, with the input exposed on the side of the drive, with the only protection against pulling the wimpy thing out a little sticker holding the wire down.
The only real advice I would give is to have a digital camera on hand while you disassemble the PS3 to help you remember certain small parts like ribbon connectors, clips and screws, go when you're putting it back together.
Other than that, follow the YLOD directions, keep all of the little screws organized, and you'll be fine.