Perhaps running pumps that move around coolant passing over the cubes of GPUs? ..
That would be extra weight/cost into orbit though...
Also, don't solar panels have reduced efficiency when they're hot? And having anything hot surely increases failure rates.. with metals getting closer to melting points...?
Ideally this is a static structure with an equilibrium temperature acceptable for the silicone to operate. If the required panel area is too hot on its own then a perpendicular cooling fin on the back that falls entirely within the shadow is added.