For our temperature testing, we measure the peak GPU core temperature under load. A reading under load comes from running Metro Exodus Enhanced Edition for 30 minutes.
As for thermal performance, we can see competitive results from the GameRock OC. Using the Performance BIOS, the GPU peaked at 63.3C, while the Silent BIOS was only about 1C hotter. It may not be the outright coolest-running card, but it's hard to argue with thermal performance at sub-65C levels either way!