Practical: The Argument for Part-Time Cryptocurrency Mining

8 min readFeb 15, 2021

Why there’s very little reason not to be mining Ethereum right now, especially if you have a current generation GPU

Update 03/16/2021

So it seems like Linus was thinking the same thing, and ended up with quite the controversial video on it. But that aside, I’ve switched over to Trexminer as it has higher hashrates and supports multi-GPU setups far better. I’ve also fixed my VRAM cooling issue completely by using much higher quality thermal pads from Fujipoly and Thermalright. The re-padding alone dropped my VRAM temperatures from almost 100C @ 100MH to 90C @ 120MH. I strongly suggest people with the 3080 or 3090 (particularly these as the rear vram modules are typically very poorly cooled) to do this, if they trust themselves to disassemble the card. It’s actually relatively easy.

Introduction

Up until the end of last year, I’ve never really involved myself much with cryptocurrency. I had a small amount invested, and still considered it a novelty mostly because I just didn’t really understand it or its implications. That changed a bit when I came across this excellent article, and began to investigate its virtues more thoroughly with white papers and and news. I’m certainly not an expert in blockchain technology, but after performing quite a bit of due diligence, I’ve begun to take cryptocurrency as a whole much more seriously. This resulting composition is not so much a get rich quick scheme, but rather a minor benefit that most people with a PC can probably take advantage of after my own experience with it.

Why Now?

Certainly the most obvious reason is increased adoption, since a currency is only worth as much as what fiat money it can be converted to or what it can buy. I’ve also found that it poses a compelling argument as a means of money storage, if not yet spendable currency; much like precious metals/gems or stocks. However, it has the advantage of being far easier to liquidate. While there’s varying opinions on which direction the validity of cryptocurrency will go, I do believe that in some form, it will be an inevitability that can better connect markets, counter hyperinflation, and provide a faster, more trusted means of money transfer. I’m still not ready to throw all my marbles into that bucket yet, so instead of just investing money, I decided to add another approach.

Mining

There’s quite a bit of stigma associated with cryptocurrency mining, and I think some of it can be justified. From its environmental costs to reduction of GPU supply, the crypto mining industry has demonstrated significant collateral effects (particularly during Covid-19 when more people are buying graphics cards for gaming amongst an already reduced production capacity). There’s arguments to be made using the energy cost of printing money as well, but that’s not something I’ll get into here. Regardless of how people feel about the virtues of the activity itself, it’s quite profitable right now from a practical standpoint.

Why Ethereum?

Simply put, it makes the most money and sense. Bitcoin’s difficulty makes it unprofitable outside of ASICs and institutional mining, but Ethereum currently doesn’t require economies of scale or significant investment. I know people who have even invested their stimulus checks into mining hardware. I was very surprised with the results of a profitability estimate, and the only real reason it took me so long to begin was that I thought the process was far more difficult than it really was.

Math

A good place to start is to figure out how much you’d actually make from this. There’s many crypto profitability calculators on the internet, but I chose to use this one from Cryptocompare as it was the simplest and most useful for my needs. For reference, my main system has an nVidia RTX 3090 Founder’s Edition and my other has a Gigabyte Vision RTX 3070.

While the theoretical maximum hashing power of these two cards is about 120+60 Megahash (MH)/second combined, I applied more conservative adjustments to reach around 150MH/s (100MH from the 3090 and 50MH from the 3070). Considering these aren’t dedicated mining rigs and I also use them for work/play, I wanted to be more cautious and not risk damaging my hardware long term.

California electricity is relatively expensive, but since I drive an electric vehicle, PG&E allows me to be on an EV-TOU (time of use) plan where from 12am-3pm, electricity is about 17 cents/kwh. In contrast, daytime peak use costs anywhere from 37–49 cents/kwh, depending on the season. The GPUs themselves run about 300 watts and 200 watts at load for the 3090 and 3070, respectively. These are just estimates, and since power targets are typically lowered for mining, the real power draw may actually be quite a bit less. I also didn’t include power consumption for the rest of the PC since I always keep mine on all the time anyway and only wanted to include additional costs. Not to mention, the GPU uses the bulk of system power while mining.

Estimated profits with my current setup from cryptocompare

Analysis

From these results, we can estimate a profit of about $14/day. Considering that I only mine for about half a day during the time that I’m sleeping or not using the PC, we can assume a profit of about $7/day based on current Ethereum rates. “Current” rate is important, since the doubling of Ether’s value this year is what ultimately helped me decide to do all of this. While I don’t expect this kind of trajectory to continue for the value of Ether, I also predict it won’t fall below $2000/Eth by the end of the year either. My plan is simply that the cards will pay for themselves, and the rest is a bonus. From a cost and efficiency standpoint, the RTX 3060Ti and 3070 are certainly the best. However, the point of this paper isn’t to advocate going out and buying a bunch of GPUs for a home mining farm, but rather that it may make sense to mine when your PC is idling (when you’re sleeping or doing office work).

Actual results of mining, from Ethermine.org

Using Ethermine’s dashboard, we can get a pretty good idea of what to expect. What’s important here is the “current hashrate,” since those are related to valid shares that you produce (which actually generate your profit). Reported hashrate is just what your GPU tells the pool. They should be relatively close, though it takes about an hour or so before the “current” catches up to “reported”. That dashboard also provides estimates in Bitcoin, USD, or Ether that you’ll make per day/week/month.

Setting Up

There many ways to set up mining for your own system, but this was my process:

I began with this Youtuber’s guide, which I found to be one of the best and easiest to follow. While lolminer isn’t the fastest nor cheapest miner, I chose it anyway as I found the difference to be negligible and it was very easy to set up. Like the video suggested, I also used Ethermine for my mining pool. However, instead of Metamask, I used a hardware wallet (Ledger Nano X).

For over/underclocking, I used MSI Afterburner with the following settings:

Additional Notes

Ether mining uses around 6–8GB of VRAM on my systems, so if you happen to run a high VRAM card like the Radeon 6000 series or an RTX 3090, you can actually have enough leftover to game on. It certainly won’t affect productivity much at all unless you’re doing photo or video editing, and I’ve found that other tasks are prioritized over mining (your hashrate will be reduced, but your experience in these other won’t really be). I’ve tested it with League of Legends and Office apps. Feel free to try others.

There is one important thing to keep in mind though, particularly for RTX 3080/3090 cards that use GDDR6X: Ethereum mining may significantly drive up your VRAM temperatures. In the case of my Founder’s Edition 3090 where some of the memory is on the back of the PCB, I’ve hit 110C and higher while mining. I wasn’t very comfortable with that, so one of the ways I found to cool the memory chips involved attaching a CPU cooler and some small heatsinks with thermal pads onto the backplate at the memory hotspots. This dropped temperatures to about 106C peak, and taking off the side panel drops it further to 104C. In the long run I may have to install liquid cooling or a custom heatsink solution, but this is how I’m currently handling it.

Modern problems require modern solutions

Not all cards have this issue, even though the GDDR6X chips themselves are known to run very hot. Some of the third-party boards have cooler designs that better contact the memory chips, so you’re in luck (or smart) if you have one of those. Not all cards have temperature sensors for the VRAM either, but if they do, you’ll see it on HWInfo readings.

Conclusion

Again, this isn’t a recommendation to go out and buy a mining rig in the hopes of getting rich. Like the title says, it’s just a practical thing to do if you happen to own one of the newest generation video cards. That’s not to say older ones won’t benefit; I just have experience with the newer ones and would rather talk about what I know. Considering that right now those GPUs are costing a premium even at “MSRP,” this is a good way to recoup some of the costs. You’re unlikely to damage your card if you do your homework, and the opposite may even be true since most mining settings undervolt. Also, I’m not keen on the tax implications of this yet either, so that’s something you may want to speak to a CPA or other expert about. What I do know that if you mine under a business entity, you’d have the option to apply hardware purchases towards business expenses and deductions.

While this isn’t a hardware review that I would typically write, I hope you’ve found it useful and informative all the same. Feel free to leave any comments or suggestions!