Sunday, April 30, 2017

How to get the fastest GPU in the world and have it pay for itself in less than six months


I wrote last month about the GTX 1080 Ti Founders Edition, and showed initial mining performance. Things are constantly in flux in the world of cryptocurrency, so what was once a great idea may suddenly become a terrible plan. Or, as is the case here, a decent idea can suddenly turn into an awesome idea.

I've got a pair of GTX 1080 Ti cards, chugging happily away. I conservatively estimated income for each card at about $3 per day (minimum), but that's proving far too pessimistic. Right now, I'm seeing income of anywhere between $4.50 at a minimum to as much as $7.50 maximum. Now, the maximum isn't likely to last for days at a time, but on average you can probably count on $4.50-$5.00 per day of net profit.

I'm partial to the non-reference designs for a variety of reasons, and my second card is the MSI GTX 1080 Ti Gaming X 11G. This is a large, heavily factory overclocked 1080 Ti. Check this out:

These are two examples taken during the past day of how the 1080 Ti is doing. $5.25 to $5.90 per day would mean that you can buy for a $740 and have it pay for itself in 140 days at a moderate return, or it might do even better and earn that back in just 125 days. That's four months to earn back the cost, after which the card is purely profit. Power costs are a factor, though, which means subtract about $0.60 per day from the earnings. You're still looking at breaking even in less than six months, easy!

But why not go the other way, and buy four cards for a single system, a 1350W PSU, and you're still looking at ROI in six months or less. The difference is that with four cards cranking away, once you hit ROI you're looking at around $21 extra in income each day, every day. Could you use $600 a month in spending money? I know I could! How about $2,400 extra a month? Build four such mining rigs!

And it really is that easy. I'm not saying the 1080 Ti is the best mining card on the planet, but it's super fast and you can do four cards per PC instead of trying for six cards. That's a bit less management headache.

Just a final caveat: don't plan on running 20 or more of these systems in your home. Each one would use over 1000W of power, and on a typical 200A circuit you're limited to 24,000W on the entire circuit -- total! You still need to account for lights, appliances, etc. And if you're on a 150A or 100A circuit breaker, you'll have to get by with half of that. Also: fire hazard. Still, doing 5-10 systems is certainly possible.

Here's the quick math:
Basic PC setup: $870 (no case -- use a wire shelf)
Ryzen 5 1600: $230
Asus Prime-X370 Pro motherboard: $150
16GB DDR4-2667: $97
240GB SSD: $63 (boot faster, install updates faster)
1200W Titanium PSU: $280 (efficiency is really important!)
PCIe riser adapters: $50 (don't use the SATA to Molex power adapter, though!)

Four GTX 1080 Ti cards: starting at $680 each = $2,720
Total = $3,590, income of $20 per day = 180 days to ROI
Five PCs = $17,950, income of $100 per day. Still 180 days to ROI
Ten PCs = $35,900, income of $200 per day. Still 180 days to payoff!

More importantly, once the initial hardware has paid for itself, you're not earning $6,300 per month. Okay, maybe more, maybe less. It doesn't matter too much, as bottom line is you have a very nice salary that will continue to pay you with little to no additional effort.

If you're the enterprising type, maybe rent a warehouse with a couple of 200A circuits and plunk down $150K on forty crazy powerful PCs. Then earn $800 per day, 365 days per year, and you'd have the equivalent of a $292K salary. Ha. But I'd suggest starting smaller and working your way up to that level, rather than jumping in whole hog. And don't be surprised if the market shifts and you see profits drop by half!

Radeon RX 570 4GB Mining Performance

Going along with my testing of RX 580 8GB mining performance, I also have a shiny new Asus RX 570 4GB card. It's running in the same Core i5-7500 system as the 580, so as you might expect the numbers are similar overall -- just lower. Here's how the card performs, at the stock OC, on the various current algorithms:
Again, DaggerHashimoto numbers are pretty low. I could try VBIOS flashing or various other tweaks, but this is running NiceHashMiner, and of course the RX 570 requires AMD's latest drivers -- which tend to not be as optimal for mining as some of the older drivers.

Based on the current numbers, looking at WhatToMine, you'll gross about $2.00-$2.25 per day, with a power draw of around 125W per card. With a power cost of $0.10 per kWh that puts net earnings at about $1.80-$2.00 per day. The Asus card sells for $190, so you'll hit ROI in about 100 days. This is a really great result, and it's why the 470 and now 570 are some of the best GPUs for cryptocurrency mining. Power draw is a bit less than the 580, prices are a bit lower, and performance is a bit lower.

You'll want to shop around a bit, and potentially other systems could run this same GPU 5-10 percent faster. It's just sort of 'luck of the draw' combined with CPU and platform factors. As with the 580, you could run up to six RX 570 cards in a single rig without too much difficulty. Getting a good 1200W or higher Platinum or Titanium rated PSU is recommended -- Rosewill's 1200W Tokamak is another decent alternative, with a few quirks (like no power switch).

Radeon RX 580 8GB Mining Performance

I like to test out new graphics cards with Bitcoin mining, and on the hotseat today is AMD's new Radeon RX 580 8GB. I'm not Bitcoin directly, obviously, but using the cards for mining altcoins via NiceHash. The recent upward trend in Bitcoin prices -- 25 percent during the month of April 2017! -- has definitely helped my bottom line, but over the long term, what will really matter is the performance and power use.

I've also found it's difficult to get a clear view of mining performance from the various GPUs. People will show results from heavily overclocked cards, results that are not long-term stable in my experience. This is stupid. If you modify your VBIOS to use tighter latencies on the GDDR5, it can improve performance by 5-10 percent ... and a few weeks later your cards will all start failing. I've been there with the RX 480, and all that downtime just isn't worth the hassle!

My advice is simple: buy a factory overclocked card with a massive cooler, use PCIe risers to separate the cards from each other, and then just run at the default clocks. The cards will run stable, at reasonable temperatures, and you're on your way to profitability. In fact, rather than overclocking, sometimes it's better to underclock and undervolt your card, to reduce power and temperatures. You're far less likely to burn out a fan, or overheat, or any number of other potential problems.

Okay, let's get on to the RX 580 8GB. I'm using the Asus ROS RX 480 Gaming OC, and absolutely massive card that's bigger than many GTX 1080 models. The benefit is it has three large fans, the cooler keeps things frosty, and it comes with a healthy factory overclock. It uses a single 8-pin power connector, and in practice if you install it in a case, you'll use three slots -- you really can't put anything into the two adjacent slots due to the size of the cooler.

And here's how the card performs, at the stock OC, on the various current algorithms:
You'll notice perhaps that the DaggerHashimoto numbers are pretty low, which is basically variance between GDDR5 types, memory subtimings, and the test system. In this case, I'm running the RX 580 on a Core i5-7500 with a B250 motherboard. That might be a factor, or it might just be a combination of relatively early hardware and the lack of specific tuning for the RX 580. You might think the 580 and 480 are the same hardware and should perform the same, but in practice there are all sorts of contributing factors. As an example, I have an RX 470 card that does 29 MH/s -- at stock factory settings! -- for DaggerHashimoto. (The card is no longer in stock anywhere and tended to sell for $240+ if you're wondering.)

Anyway, based on the current numbers, you'll earn about $2.25-$2.75 per day, with a power draw of around 150W per card. With a power cost of $0.10 per kWh that puts net earnings at about $2.00-$2.40 per day. In the case of the Asus card, which sells for $280, you'll hit ROI in about 140 days, which is a really great result.

This is with one of the most expensive RX 580 cards, of course, and you could drop to a 4GB model without really losing any performance. As an alternative to the Asus, the MSI RX 580 Gaming X 4G costs just $215, and it has similar clockspeeds in the default 'Gaming' mode. ROI on a card like this is only 100-110 days, conservatively -- and if Bitcoin prices improve, you might hit ROI in as few as 60 days. Or things could go the other way and it might take 200 days.

Overall, the RX 580 is one of the best options for cryptocurrency mining right now. With a single 8-pin connector, it makes it relatively easy to put four or even six GPUs into a single mining rig. I recommend getting a great power supply for such a configuration, with the Enermax Platimax 1350W sitting at the top of my list.