kenmgrimm wrote:
I tried everything on this thread including gfxCardStatus and various Energy Saver settings. Nothing worked but I did get my computer functioning again when I restored it entirely to Mavericks. I really hope that the rest of you guys have a full backup because your computer is a brick unless if you can do this.
This is such **** poor QA by Apple that they didn't catch this. I was really worried that I would have permanent hardware failure being that the thing was constantly overheating, locking up, refusing to boot. I'm a huge Apple fan but the way they handle things like this is ********. Acknowledge the problem, suggest workarounds, allow users to bring in the macbooks to the Apple Store free of charge and get this FIXED.
Stop freaking out and take the right actions.
I had your exact same problem when first installed Yosemite on the very same laptop. It was a fresh install. At the second attempt everything went fine.
My suggestion is to do a clean fresh install using the LATEST version, 10.10.2. There a a bunch of tutorials online about how to make a bootable Yosemite install usb thumb drive (I used an SD Card).
One more thing: You'll still have some issues with graphic slowdowns when connected to an external display. But you can address those too.
I'm afraid the Yosemite release was a little too fast than it was supposed to, and I'm also surprised and a bit suspicious about the beta testing which was done with real users prior its release. It looks like no one with our machines reported these problems. Pretty strange.