Hurrah!
The lesson here is that people who own a cool, overclockable GPU in a gaming laptop may want to overclock it. Goodness knows what came over them when they removed it, but at least they've seen sense now.
FWIW, the GM204 chip runs cool and is easy to overclock. I overclocked my 980M from 1,038 MHz (core), 1,253 MHz (RAM) to 1,228 MHz (core), 1,373 MHz (RAM) and received an 8% boost in my 3DMark scores. The GPU temperature didn't go above 70C either.
It makes a noticeable difference playing games at 3K, which is the native resolution of the panel.
For those who are unaware btw, if the chip gets too hot it'll simply downclock until it reaches a stable temperature. In some brands of laptop that happens at stock speeds, whereas others (such as the Clevo I have) have plenty of headroom. It's not the sort of thing that's going to lead to warranty repairs.