A firmware update (dated 1/15/2015) was installed lest night and it fixed my heat/fan problem.
It still gets up to 180º when running a video, but otherwise has stayed <130º even with Photoshop 7.0 applying a filter, Word and a few IE windows open. And no fan, just quiet. Now I can actually use Win10 as my default OS.
I was expecting to have to wait till the Consumer Preview version to get the problem fixed, but a firmware update fixed it.
That raises a question I have. Firmware updates affect the flash memory the SP3 uses to boot, before the OS loads, right?
I had a firmware update for win8.1 several days ago, and now one in Win10. Would changes made for Win10 affect Win8 or vice versa?