What are normal *safe* temperatures for the R1?

What are the expected normal temperatures I should see out of the R1's GPU and CPU?

Like what are normal Idle/low/light use temps. Then what are normal temps to see under heavy load for extended periods?

The only reason why I am weary is because I had a 2011 iMac with integrated graphics that would constantly hover around 70 idle-90 load* and it eventually lead to the graphics card failure.

Since the alpha is far easier to service, I would like to know when would be the optimal time to perform maintainence, such as thermal compound replacement and dust clearing.