Last week I got Macs Fan Control to monitor the CPU temp. and I can confirm that 10.10.3 is causing my Mac to run too hot: I was playing Flash video today (Safari) and doing other things and my Mac shut itself off today. I started it back up and it got things going again and I watched the temp., it was hovering around 88ºC with the fan at max. speed, and I think it shuts down over 90º? So, 10.10.3 is doing something with graphics that is causing the processor to be getting too hot? (NOTE: this is also with the new Safari update.) Previously, I think the OS would do something to prevent overheating, but, ????? This has only been happening w/10.10.3, not any previous OS X, on this Mac, ever. (me: 2010 MBP 13") I've also has lockups w/10.10.3 (and not any previous OS X on this Mac). When a Mac shuts itself off, it's typically because the CPU is overheating, to prevent damage. So, it's not a hardware issue, nor is it specific to one Mac, I also see other posts w/similar issues on other Macs some say are related to graphics. (Crashes, kernel panics, lockups, warmer/hotter, shut itself off.). EDIT: I see these mostly posted in hardware forums. I hope apple addresses this w/10.10.4. I've seriously not had this Mac taken down like this.