The RPi 3 & 4 run hot. A side effect of the heat is the slow-down in performance as the CPU clock scales down to prevent permanent damage. To cool the ICs, it is important to 1) transfer the heat into a secondary mass, 2) dissipate the heat from the secondary mass. These tiny blocks of aluminium are fine as Secondary Mass.
The blocks come with a black adhesive tape (like double-sided tape), that is also good at thermal conductivity. You should not peel it away. I cut out square holes in the tape and filled it with a tiny amount of thermal transfer paste. This has the effect that more heat is transferred to the heat-sink (due to the thermal transfer paste), but the heat sink remains stuck to the CPU (due to the remaining tape). I addition, I also used a tiny amount of super-glue to provide additional 'stickyness'.
The heat-sinks are no longer in the desired combination for Raspberry Pi 4. The new RPi4 has many ICs that run super-hot. Chief among them are the Power-Converter near the USB-C power input, the Gigabit Ethernet controller, the USB-3 controller, the RAM package, the CPU package. Fortunately, all the critical ICs are on the top-side of the board now. I ended up using more than one of this set to cool the entire board, thus doubling the cost.
Also, because I used a cooling fan, I did not use the largest heat-sink to cool the CPU and stuck it on the RAM package instead. By very carefully positioning the fan, I was able to blow air directly on the CPU package (which already features a metal plate), and also fit the fan into the case.
Let me know if this review was helpful.
|Item Weight||10 g|
|Package Dimensions||8.6 x 5.7 x 1.1 cm; 10 Grams|