Conclusion
While life isn't always black and white, you could say that overclocking Ryzen CPUs using LN2 is definitely cut-and-dried. On one hand, you have some processors that handle cryogenic temperatures and high voltages without a problem. They can reboot without issue at -196°C, allowing you to continue your pursuit of higher clock rates. In other words, they're every overclocker's dream.
But some Ryzen processors are stubborn to the point of being nightmarish. Having to go from -196°C to -20°C after every crash is not pleasurable. The resulting consumption of nitrogen, gas, and patience is downright frustrating.
AMD's Selection Methodology
Enthusiasts in the habit of trying multiple CPUs and keeping only the best won't be bothered. They'll toss stubborn samples aside for someone else to worry about. But if you're on a budget and only have one processor to experiment with, the luck of the draw is particularly unforgiving right now.
Strangely enough, while we expected the processors with the fewest cores to overclock best, the opposite proved true. With only 10 samples on-hand, it's hard to draw statistically reliable conclusions. According to our tests, though, the Ryzen 5 CPUs couldn't stand up to the clock rates achieved by our Ryzen 7s. This is most certainly due to AMD's binning process. Lower-performing chips have some cores deactivated and their clock rates reduced. The best dies go into the Ryzen 7 1800X model.
Thus, your best bet for a good overclock under LN2 is AMD's Ryzen 7 1800X. In our air cooling tests, one Ryzen 7 1700 was able to keep up with the 1800Xes.
Ultra-Solid Processors
To end on a positive note, we want to emphasize that, despite tens of hours testing with liquid nitrogen cooling, using high voltages at cryogenic temperatures, and building/tearing down our test platform (with water everywhere), not a single component was damaged. Ryzen appears solid, despite its relative youth. And when you stumble across a gem of a sample, it's a pleasure to overclock.
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