The effectiveness of the device/heatsink interface is determined solely by the thermal pad, so the size of the heatsink doesn't affect that part of the equation. What does help is lots of heatsink surface area. That's why I'd always recommend an aluminium heatsink case over anything else as it has a very high surface area to volume ratio whilst staying mostly within the Pi's footprint if you buy a low profile version.Ah, right, thank you.
That has saved me loads of reading. I assumed it would make more of a difference.
Oooh, decisions decisions.
I wonder how much difference there is with passive heatsinks.
The larger the heatsink, the less air you need to pass over it for the same drop in temperature. That's why they work so well passively. I've been experimenting with blowing air over mine with a Gelid Solutions 'Silent 6' 60mm 12V fan running from 5V and seeing temperature drops of up to 20°C. As I'm sure you can imagine, a fan that's designed to be very quiet at 12V is as close to silent as makes no difference at 5V.
If you're handy with swapping pins around in standard 3-pin PC fan plugs, it's possible to fit one on to the 0V and 5V pins on the Pi's GPIO header. No soldering required. Incidentally, the 'Silent 6' only draws around 50mA (0.25W) at 5V, so it's perfectly safe to do this.
Note: Not all 12V fans will run from 5V so, if you go this route, choose your fan carefully.
Statistics: Posted by GTR2Fan — Tue Mar 05, 2024 12:47 pm