Bring on the Cold
We fill up an inox thermos can with Liquid Nitrogen to make it easier to handle; the can doesn’t become very cold and can easily be handled with bare hands.
Watch out for frostbite
We drilled a small hole in the base middle of the container so we could insert a temp probe
The temperature readings we got were quite impressive and promising:
Since LN2 evaporates quite quickly we focused on calculating SuperPI 1MB as fast as possible; our first result we obtained with the CPU running at 3650Mhz
However a multiplier bug holds us back from setting high memory frequencies which impacts score quite a bit; a few liters of LN2 later we were able to increase CPU speed to 3868Mhz, not quite the 4Ghz mark but we’re closing in.
At this speed SuperPI is calculated in 20.xx seconds!
After 7 hours of benchmarking at these -190°C temperatures we still had a working system, which meant our condensation steps were well worth it.
A last shot of the LN2 freezing the CPU:
On the next page we dissemble the system and clean up the motherboard ->