The Raspberry Pi 4 needs a fan
Quote:<p><pre><code>  the metal casing helps
  spread that heat around
</code></pre>
It does, to a degree. But that is absolutely not what we are seeing in that IR picture. Shiny bare metal is a mirror at the wavelengths that thermal camera uses. So what you see on thermal image where wifi-module shield and CPU are is reflection of ambient (room) where this picture was taken. Try waving your hand around, you'll see it reflecting there too.<p>To measure real metal surface temperature by IR, you have to paint that metal (ideally, with black matte paint), or apply similarly-textured sticker.