Hackers have a long history of overclocking CPUs ranging from desktop computers to Arduinos. [Jacken] wanted a little more oomph for his
Pi Zero-Raspberry Pi-based media center, so he naturally wanted to boost the clock frequency. Like most overclocking though, the biggest limit is how much heat you can dump off the chip.
[Jacken] removed the normal heat sink and built a new one out of inexpensive copper shim, thermal compound, and super glue. The result isn’t very pretty, but it does let him run the
Zero Pi at 1.5 GHz reliably. The heat sink is very low profile and doesn’t interfere with plugging other things into the board. Naturally, your results may vary on clock frequency and stability.
[Jacken] staggers the shim pieces to afford more exposed surface area. Although copper is a good conductor of heat, using multiple pieces probably mitigates some of the advantage. On the other hand, using thermal compound between the pieces should reduce the microgaps between shims, so that will help.
In addition to overclocking, [Jacken] made some power measurements with all cores active and came up with a surprisingly low current draw (well under 1A). That’s a sample of one, though, so you should probably make your own measurements if it matters
This isn’t the first [Jacken] overclock we’ve seen but the new aspect is the low profile heat sink. If you are just in it for sport, you can overclock an Arduino, even. You can run at 65 MHz, as long as you don’t mind supply liquid nitrogen.