Building the Ghetto rig

My original plan was to:

  1. Mine some ETH with my gaming PC.
  2. Sell ETH for fiat currency on Kraken.
  3. Transfer money to my regular bank account.
  4. Build a proper rig.

More power

Check, check, check and now working on number 4. I got together with two friends and made an investment:

hardware for the ghetto rig

Hardware for the ghetto rig

We went with similar parts to what I used in my gaming PC with some exceptions.

  • Core i3 CPU. Cheap and doesn’t use much power, but not completely worthless. One could use even cheaper CPUs but we reasoned that since we might need to repurpose the rig in the not so distant future that might not be optimal.
  • ASUS z270-P motherboard. This guy managed to build a 8 GPU rig with it so it should work for our initial 6 GPU build.
  • 6x MSI GeForce GTX 1060 6GB OC. Cards are getting increasingly hard to find. This was the only 1060 model we found that we could buy six of. AMD cards haven’t been available for months, otherwise there might have been more value in rx570 cards.
  • Corsair RM750x PSU. This could be where we failed some. If we would be able to connect all GPUs to this PSU we might put to much strain on it. Each of those GPUs will use 85-100W and then you need some for the rest of the hardware. There is a plan B and C though. We have a 1050W PSU available that’s not being used to its’ full potential and we might swap that one for this RM750x. Plan C would be to fit in a secondary PSU and use two in the rig. The PSU situation is the same as with the GPUs, there are just no powerful PSUs in stock at the moment.
  • 2×4 GB Corsair Vengance DDR4. Maybe more than we need but same reasoning here as with the CPU.
  • Cheap WD Green SSD

Since we didn’t buy a case we also needed a power button. I ordered this from AliExpress a couple of weeks ago:

power button

Power button for when you don’t have a case

To be able to connect 6 GPUs to one motherboard you also need PCI-E risers. There are two PCI-E x16 and four PCI-E x1 slots on the board and with these risers you can connect x16 cards to x1 slots. The risers also makes it possible to get the cards (and heat) away from each other which is vital. They haven’t arrived yet though so for now we will only install two cards in the two available 16x slots.

pci-e risers

Risers that connects x16 cards to x1 slots

Putting things togheter

Inspired by all the milk crate rigs you find on the Internet, we went with this:

ghetto case

the ghetto case

It isn’t very well ventilated so we needed to do some work on it, but the motherboard and PSU went magically well inside:

z270-P and RX750 in case

z270-P and RM750x in case

ventilation for psu

Ghetto style ventilation for PSU

modded case

case modded and parts some fitted

pulp ball

To put some distance between the case and the motherboard we needed to raid my five year old daughters room for some ordinary pulp balls. I admit, we came pretty unprepared for this step but it worked out great. Six screws, each through the motherboard and the case with one pulp ball between the case and board. On the bottom where the screws were sticking out we put more pulp balls to hide the screws and get feet for the case. We also used them as distances between the side of the case and the PSU and then secured the PSU with a cable tie. Success.

the ghetto rig

the ghetto rig with two 1060 cards fitted

Once the GPUs where in place we slapped an old case fan directly to the cards to help further with driving out hot air in between.

Results

rig up and running

The ghetto rig up and running

It’s alive! And also mining ETH. We tweaked the cards with MSI Afterburner (power target 70%, memory clock up) and were getting ~23 MH/s per card at less than 60C temperatures after 6+ hours of mining.

ghettominer mining

Getting ~46 MH/s average hashrate

What we need to do next is to wait for risers to arrive, solve the PSU situation and modify the case to support four more cards.

Money in the bank

I finally got tier 2 verification on Kraken which meant that the whole “from mining to money” process should be working.

Recipe for making your GPU buy you beer in 12 easy steps

  1. Download and install Mist and create a new Ethereum address. Be prepared to struggle some when syncing with the chain and keep the developers tools console open to see when/if things fail. I guess UX isn’t yet a top priority.
  2. Protect your encrypted key files and your password. Losing them means losing control over your funds.
  3. Install a miner such as Claymore.
  4. Tune your GPU for mining.
  5. Join a mining pool such as Nanopool or Dwarfpool and start mining. Eventually you will get a payout and have a balance on your address.
  6. Join an exchange such as Kraken so that you can trade crypto for your currency of choice. In fact, do this as early as possible since it takes time to get verified for fiat currency deposits and withdrawals. Maybe I was unlucky but it took me three weeks. After getting in touch with them on Twitter they fixed my verification within minutes though.
  7. Generate a deposit address on Kraken so that you can deposit the Ether you’ve mined.
  8. Transfer some ETH using Mist from your address to your new Kraken address.
  9. Sell ETH for EUR (or whatever is convenient for you).

    selling some eth on kraken

    selling some eth on kraken

  10. Set up your regular bank account in Kraken for withdrawals and make a SEPA transaction.

    SEPA withdrawal confirmed in kraken

    SEPA withdrawal confirmed in kraken

  11. Wait a day or two (actually took less than 24 hours in my case) and voila, money:

    SEPA transaction

    Incoming payment from Kraken to my regular bank account

  12. Buy beer
beer bought by profits from mining

Beer bought with profits from mining. Also more 1060s. We’re putting together a rig.

Rinse, repeat, buy more hardware and mine until the Ice Age hits or Casper makes mining obsolete. Then switch to mining a new crypto currency if there are any profitable ones left or sell your GPUs and short the NVIDIA stock since the second hand market will be flooded with hardware.

Tuning the ASUS 1060 DUAL 6GB GPU for Ether mining

When mining for ETH you really want to get the most hashes per second at the lowest power consumption possible. There are a couple of calculators out there to help you play around with these parameters and see what kind of profit you would be getting.

I bought a power meter and plugged it in to see how much power my rig was consuming when mining. I also installed ASUS GPU Tweak II to be able to control some parameters of the ASUS 1060 DUAL 6GB GPU and HWInfo to get more detailed reading on memory frequencies, temperatures and power consumption. This was from running on stock settings:

mining on 1060 DUAL 6GB on stock settings

mining on 1060 DUAL 6GB on stock settings

consuming ~138w when mining on stock settings

consuming ~138W when mining on stock settings

I was getting out ~19 MH/s from the card and reaching temperatures of around 66C. The machine consumed about 138W and the GPU was using 100W.

It turns out, these stock settings are not optimal for mining as described in this article. You can lower the power target of the GPU and boost the memory clock significantly to get higher hash rates at lower temperatures and lower power consumption! Almost sounds to good to be true, but have a look:

mining on 1060 DUAL 6GB on modified settings

mining on 1060 DUAL 6GB on modified settings

consuming ~119w when mining on modified settings

consuming ~119W when mining on modified settings

I was now mining at ~22MH/s at 60C and only consuming 119W instead of 138W and the GPU only drawing 82W. The conclusion is that tuning matters, a lot! Numbers add up quickly when you have a mining rig running 24/7.

I played around a bit with the parameters of GPU Tweak II and found that the memory clock is the one that counts when it comes to hashrate. Underclocking it by 1500 Mhz got me a hashrate of ~12,2MH/s and overclocking it by 1500 MHz got me to 22 MH/s. The power target parameter mainly affected the power consumption, although bringing it down to 50% killed the hashrate as well. Setting the power target at 70% got me the best hashrate per Watt ratio. The GPU Voltage and GPU Boost Clock parameters didn’t do much for the hashrate at all.

Also, it looks like I’m not really utilizing my 750W gold rated PSU. I might try sticking in one more 1060 GPU in there. I wont be able to run the cards in SLI so it won’t improve gaming performance, but it would double the hash rate when mining.