A most useful thread, thank you all, along with the mass of information at
https://www.raspberrypi.org/forums/vie ... 8&t=243500
. I'm most impressed with the Pi4, as a desktop replacement but am concerned over the heat issue. I know that the 'experts' say don't worry, but as an Electronic Engineer, I am uncomfortable running CPUs continuously at some of the temperatures recorded in these threads.
I have tried 3 RPi4 cases. Results of my non-scientific trial is as follows:
1. The official RPi4 case with a finned heat sink. It ran hot so I placed a small fan inside the case, using the existing ventilation holes. It now runs below 60degC, but is a bit noisy and the fan isn't secured. Works, but not recommended.
2. FLIRC. No fan, but a good thermal sink. My Pi ran up to 68deg and the case felt uncomfortably hot to the touch. I concluded that the case had insufficient thermal capacity (for my liking). I added ALDI hardware corner brackets ("ALDI Angle Set 4 piece" 2.99GBP) top and bottom, which although primitive and steel, brought the temp down into the high 40s, low 50s.
As this is tucked away behind my desk, aesthetics are not important and goes to show how additional thermal capacity, albeit crude, can help.
3. Bruphny acrylic case. This included a fan and 3 heat sinks. I consider this the best of the three cases. Nicely made: The instructions are very clear: The fan can be run at 3volt and is almost silent. At the highest, it runs in the high 50s but normally in the 40s.