Edited by tkaiser at Fri Nov 21, 2014 04:14 |
Yeah, damn right. Most if not all available cases for the Banana Pi are simply 'broken by design' regarding thermal issues (even the official ones sold by LeMaker and Banana Pi resellers) which might negatively impact performance due to throttling and the lifespan of your device (the hotter the stuff the earlier it dies).
Unlike nearly all other single board computers on the Banana Pi all the 'hot stuff' is on the bottom of the PCB so it's a really bad idea to use an enclosure where there's no air flow possible and just a few millimeters space around those components.
But the good news is: You don't need a fan consuming energy and producing noise. Just do it right and use convection. This means three things:
a) operate the Banana Pi upside down or even better vertically
b) ensure enough airflow
c) heatsinks/fans aren't necessary when you take care of a) and b)
On my Banana Pi I have an SMD heatsink on the AXP209 PMU (these are the thermal values you measure in Lubuntu! They tell you it's CPU but that's not right because SoC/CPU has its own thermal sensor). On an idle system the temperature of this power management unit is normally 6-7°C above ambient temperature and under heavy load does not exceed 14° above ambient:
Compare your 55° (in the thermally broken enclosure) with your 36° with applied fan to the 28° idle and 35° under heavy load only using passive cooling or to be more precise: a small heatsink and convection.
There's no need for a fan unless you use bad enclosures that ignore the Banana Pi's thermal challenges