Understanding why custom firmware is one of the most important tools available to miners for improving the productivity and lifespan on ASIC mining machines.
The first batches of the Antminer S9 were shipped in 2016—about 5 years ago from the time of publishing this article. They have proven to be incredibly durable mining rigs, with low failure rates even after years of wear and tear in tough conditions such as dusty oil fields and freezing cold tundras.
However, we can’t really expect that S9’s will keep running forever. For the earliest batches and the ones that haven’t received quality maintenance, failures are starting to occur at higher rates. Miners who still rely heavily on these old-generation rigs must take extra care to preserve their lifespan and keep them hashing until the next halving, and maybe even beyond.
One of the most important tools miners have in order to extend hardware lifespan is also the one they most commonly associate with the opposite effect: custom ASIC firmware. While most of the attention usually goes to overclocking—a practice which maximizes hashrate but decreases ASIC lifespan—autotuning firmware can also be extremely useful to Antminer S9 and S17 owners who want to maximize their profitability per Watt of energy consumed and increase their ASIC lifespan at the same time.
ASIC hardware is not built to last forever, no matter how well you maintain it. However, it’s important to understand what causes mining rig performance to deteriorate over time and ultimately fail, assuming that you avoid the more obvious failures like overheating and burning hashboards of course.
Firstly, we have to understand the effect of temperature fluctuations in the environment. For air cooled machines, rapid variations in outside temperature can cause all the parts in the ASIC to expand and contract at different rates. For example, the silicon hashing chips respond differently to temperature changes than the copper and aluminum conductors, causing general wear and tear that can ultimately lead to mechanical failure.
In addition to those temperature fluctuations, small but constant vibrations can gradually wear down the parts in the mining rig. The primary cause of these vibrations is the fans used for cooling, as they are the only real “moving” part in the hardware. If you’re in a hot environment and running your ASICs at full capacity or even overclocking, it likely means you’ll have to run the fans at higher RPM’s, leading to stronger vibrations.
One of the best solutions to both of these issues is immersion cooling, as the dielectric coolant used in immersion systems has a far greater thermal density than air, thus preventing rapid temperature fluctuations. Additionally, you no longer need to run fans when your mining rigs are immersed, meaning that the hardware will not be subject to much movement or vibrations.
The problem with immersion, of course, is the cost. It’s extremely expensive compared to air cooling, and probably not an economically viable solution for use with older hardware like the Antminer S9. So, when immersion isn’t an option, what else can be done to improve ASIC lifespan?
With temperature fluctuations and vibrations being the main factors that degrade ASIC lifespan long-term, minimizing those two things is the key to giving your machines longevity. The surest way to do that is by running your ASICs at lower power inputs, something which is enabled with custom firmwares just like overclocking.
For example, an Antminer S9 with Braiins OS+ firmware can have a power consumption anywhere between 400 W - 1800 W. At lower power limits, the machine doesn’t produce as much heat and, as a result, the fans don’t need to spin as fast. With lower fan speeds, the machines will vibrate less and also be a lot quieter.
Meanwhile, lower temperatures on the hashboards are likely to be much closer to the ambient temperature of the surroundings. Having a smaller difference in those temperatures should result in less fluctuations and thus less wear and tear on the different components in the hardware, extending its lifespan long-term.
Perhaps the best part is that these lower power consumption levels also result in the mining rigs operating more efficiently (i.e. better W/TH/s). For example, in the image at the beginning of this section, the Antminer S9 is producing 13.09 TH/s at 1 kW, for an efficiency of just under 76 W/TH/s. Stock specifications for an S9 are 13.5 TH/s at 1160 W (efficiency 86 W/TH/s), so this Braiins OS+ setting consumes 160 fewer Watts but still nearly produces the same hashrate.
Final thought: if you have slim profit margins or simply want to minimize your operating expenses, running on lower power inputs is best both short-term and long-term.
Bitcoin mining software company: Braiins Pool, Braiins OS+ & Stratum V2.
By miners, for miners.