I just installed 10.10 on my girlfriends Toshiba Satellite a300 and for about two days it has been working just fine for two days but today it started acting pretty wonky.
Several times over the machine just dies as if it didn't have a battery and someone yanked out the power supply. After such a crash I'll have to wait a while before powering it up again or it will die before it even reaches the startup screen.
It sort of seems like it's reacting to something I do. I kept it on for several hours while we were out of the house and it was still fine when I came back. I haven't been doing anything I can imagine is especially CPU-intensive when the crashes occur, but I have been trying to set up her iPod with Rythmbox and / or Banshee.
If anyone can point me in the right direction I'd be very grateful.