Rebuilt case with additional Noctua NF-A9 PWM fan. Compared to the original case, the temperature dropped by 5°C. The original idea was to replace the internal fan with a Noctua A9 5V, but it was hard to find, so I used a 12V fan I had lying around at home and added it to the original cooling. It is powered from the rear USB port via a MT3602 step-up converter, I drilled a hole for the cable with a 5mm drill. I set the voltage to less than 12V so that the fan was inaudible. I used the bottom part of the original case with rubber feet to cover the board.