70C. The chip is rated to 85C, what temperature were you at at 600mhz
implemented various implementation strategies to cherry pick get a good bitstream running stable at 550MHz+.
The temperature is between 30 to 45 C depending on the time of day. My KC705 came with a heatsink + fan though.
Hmm, I used exactly you vivado project to create an bitstream. But the temparature is near by 76-78 °C realted to my room temperature (24 °C at the moment):
2013-05-24 01:20:10.619202 [500] stdout: ('Temperature: ', 76.9086849212647)
I'm still on 600 MHz at the moment because it looks like stable.
In my opinion we should switch the clock frequency dynamicable to an less value if the temp will increase over an limit, e.g. 80 °C. What do you think? It should not be so hard to do that.
My heatsink + fan looks like the same as on your pictures.