Building an Ethereum Mining Rig

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For the first time, I am building a ethereum mining rig myself and now I want to share my experience with you. For the case, I have used a very simple wood construction for less than 10€. Here is the sketch:


And this is how it looks like:


]2 Mining Rig, first draft

The following hardware has been used:

  • ASRock H61 BTC Pro
  • Intel Celeron Dualcore CPU
  • Cheapo 2x4GB RAM
  • 6x cheap powered rises for about 5€ from ebay (I later cut some loose cable endings just to make sure there are no short circuits)
  • 2x Corsair CX750M 750W PSUs

As for the graphics cards:

  • 3x Sapphire Radeon HD 7970 @ 1050/1375
  • 2x Club 3D Radeon HD 7950 @ 880/1250
  • 1x MSI Lightning Radeon HD 7970 @ 1200/1500

I have benchmarked the single cards as well as the temperature in a closed room after the rig has been running all night.

Adapter 0 – Sapphire 7970 @ 1050 / 1375: 24,0 MH/s Sensor 0: Temperature – 83.00 C

Adapter 1 – Club 3D 7950 @ 925 / 1250: 21,9 MH/s Sensor 0: Temperature – 88.00 C

Adapter 2 – Club 3D 7950 @ 925 / 1250: 22,2 MH/s Sensor 0: Temperature – 82.00 C

Adapter 3 – Sapphire 7970 @ 1050 / 1375: 25,4 MH/s Sensor 0: Temperature – 78.00 C

Adapter 4 – Sapphire 7970 @ 1050 / 1375: 24,4 MH/s Sensor 0: Temperature – 82.00 C

Adapter 5 – MSI Lightning 7970 @ 1200 / 1500: 28,9 MH/s Sensor 0: Temperature – 76.00 C

The system a total power consumption of about 1440 Watts at the wall (230VAC), delivering a stable hashrate of ~147MH/s. As I bought almost all parts used, I paid about 900€ for the complete rig.

What would I do different now? First off, I would make the feet of the rig stand out at the bottom, so it is stackable. Probably it is also a better idea to have the PSUs on the outside of the rig. For mounting the cards, I have better used M3 screws, and the cards should no hang as high as they do now, because I had trouble with the first PCI-e riser on the very left being to short. Also, the conventional HDD is producing a lot of heat, SSDs are so cheap that I would definately go with one of these.


With the next rig, I will peek into how the Radeon HD 7990 performs, as those are 2x7970s on a single cards, with promising 50MH/s for about 375 Watts. The 7950’s are better on the paper, but actually they run very hot a low clocks. Changing the thermal paste to a metal liquid paste and clocking the down prevents them to go up in fire, and that’s all I can say about those. As soon as I can get some 7970s to replace them, I will do so.

If you found any of this useful, you might send a tip: 0xa28f8098a723e4ca02e9f4512410c519a252c1a9


My PSUs don’t have six PCI-E connectors. I have used adapter to squeeze out 2 additional ones on each, but I made sure that every cards a least gets a main PCI-E power connector (ie. two cards 1x PCI-E from PSU and 1x through adaptor, one card 2x PCI-E from PSU. If you have different cards, try to make the stronger ones having the two original PCI-E lines). Do not mix PCI-E lines between adaptors, keep them separated, ie. PSU1 will power cards 1-3, PSU2 will power cards 4-6. I advise using those risers with USB cables, I have both the types of risers and bought twice.

If you do not follow this wiring scheme you risk shorts or unbalanced power distribution, leading to overload and/or bad power efficiency.

Wiring plan: wiring


57 thoughts on “Building an Ethereum Mining Rig”

  1. Hi Jacob
    please contact me on my mail. I habe a gpu hash power of 47 Mhs, I would like to start ether mining.


  2. hi!: do you know if win 7 64 have a limit of videocards, because i use a h81 pro btc, and 6 gigabyte r9 380, and in windows device manager say taht 2 video cards are disable, i change the video cards and only use 4 and all work.


    what s.o. do you use?

    1. i think you have a multiple gpu on a single card needs correct driver, did you have a previously cards installed on the machine they will disable auto if they aren’t installed anymore, this is what the AMD pro said to me when it happened to me,, We are currently getting reports of stability issues with some R9 380 GPUs, apologies for any inconvenience caused.

      Some users have reported that using the latest Crimson 16.6.1 drivers has resolved the issue. If you experience the same issue with Crimson 16.6.1, please try Catalyst 15.11.1 Beta to see if that resolves the issue. it didnt work for me i had to reinstall windows to fix it there might be another driver that is incompatible with your graphics driver causing weird “unforseen” issues basically i wouldnt use the R9 serious with any other card other then a r9 series they are different tech to most cards

  3. I have been saving up parts for the last 2 years for gpu mining I currently have 10 AMD HD 7670 2GB DDR5 cards and minimal experience in mining. Just wondering how to figure out what my Hashrate would be and how to effeciently set this up. Shoot me an email buddy. Cheers.

    Considering mining other cryptocurrencies vs ether as I don’t pay for power and have interest in the future of certain currencys.

  4. While I am mining in a pool _nanopool) can I set my address to be my paper wallet; such as Will my Eth be deposited to that address and be available? Also I have 2 r9 280x’s and 1 r9 290 gpu, can I just pop those all into one mobo and mine with them even though they will not all have pcie 16x slots?

    1. No harm in trying you need A good power supply. If each gpu says it uses 250w* epect to add 10 % even 12% to its power demand. For fun try overclocking to see if your psu can survive the heat. and give its best performance b4 it fries.

      *(That may be the best “mh per watt” according to to “sales” specifications.) Im using Icarus gpus. They get very hot. The wings symbol melted off the sticker.

  5. Hey Jacob,

    Can I know will it say syncing finished after completely download the blockchain ?
    It doesn’t download properly
    Please help me

    Thank you
    Lithika Lakmina

    1. No, it will continuously sync the blockchain. You have check the block number in order to tell whether it is at the top of the chain.

  6. Hi Jacob,
    how your mining rig does affect internet speed (upload/download), what is the minimum upload/download for your mining rig to run in maximum efficiency ?
    Best regards,

  7. Hi Jacob!

    I m new in this and I want to make a rig like:

    asrock h81pro btc
    4 x r9 390x
    2xCX 750

    What u think about? And what pci-e riser i need for that?


  8. I am from germany too 🙂

    I want to build a ring with 6 r9 280x
    and unfortunately I do not have much experience.
    can you give me some tips?

  9. Thank you for sharing your rig details, looks great!
    Did you used Linux or Windows? And how exactly Ethminer.exe command looked like for 6 GPU’s? Did you used “t” parameter to specify the number of GPU’s? Thanks.

  10. HI Jacob
    I am from Cologne and I am about to try some mining the first time. I am planing to use the following setup:

    4x AMD Radeon R9 390X
    ASRock H81 Pro BTC Board
    2x Corsair CX750
    Sandisk SSD
    2x4GB DDR3
    Intel Dual Core 3,2 GHz

    Price: about 1.900€
    Hasrate: About 110 MH/s

    My questions are:
    What do oyu think of it ? 🙂
    Do you think nonpowered risers will work?
    Will a dual Dual Core be sufficient?
    I am not quiete sure how to run the dual PSUs , but will find out.

    Many thanks and best regards,

  11. Hey!

    I have a big problem! I have 2 x 7950 GPUs and ASRock H61 PRO BTC mobo. When I connect GPUs via risers i don’t have screen, monitor display “No signal”. I used HDMI cable and DVI – no results. When I connect HDMI to mobo and unplugd GPUs from mobo it works perfectly.

    Sometimes one GPU works with HDMI cable but not even. Where is the problem?? Damaged mobo? Bad risers?

    My PSU is Corsair CX750.

    1. Solved.

      Reset BIOS, format HDD and re-install windows. Now it works correct.

      But next question… Is diffrent betwee using USB riser and IDE/ATA cable?? I have 2 x 7950 and mining at dwarfpool. Current profit is ~0.9ETH/day. Average hashrate is 40,5MH/s. In each calcualtor with this hashrate profit should be 1,01ETH/day where is the problem?

      My settings:
      2 x GIGABYTE HD 7950
      ASRock H61 PRO BTC
      Corsair CX750
      Vengeance 4GB 1600MHz
      Segate 160GB 7200rpm
      Risers IDE/ATA with molex (not connected)
      Intel Celeron G1610
      Windows 8.1

      Where is the problem??

    1. I wouldn’t recommend that. I have 3 GPUs connected to such a PSU, one has two PCI-E connectors and the two other cards have one PCI-E connector plus one through a molex to PCI-E adapter.
      Molex to PCI-E

    1. Impossible to predict. That depends on the development of the price, which is very volatile. Regarding the current development, ROI when spending the amount mentioned above will probably take place after about 3 months (when you’re NOT paying for electricity).

      No guarantee on that. There are so many parameters that can change.

  12. Hi Jacob,
    Could you clarify how the gpus and cpu are wired up to the power supplies? I have practically no experience with hardware like this, and it’s not entirely clear from your photos how to set up the wiring.

  13. Did you run into any difficulties getting the GPU to run off the riser cables? I’ve tried on 2 of my rigs with 7970s and the GPUs just don’t seem to get detected by the miner (I’m using ethminer off of coinotron on win7 64bit). The GPU don’t seem to get detected by speedfan either for that matter.

    1. After changing cards, I always had to remove the xorg.conf and re-run aticonfig with the initial flag. Maybe that solves your problem, too?

  14. My dad and I want to start mining ethereum, but hearing about how fast bitcoin mining became obsolete we are a bit concerned. Can you give us an Idea with the cost involved in a setup such as this and how much ethereum you can mine? Thanks,

    1. It all depends on how much the electricity costs. You will get a 7970 (which is the card with which seems to have the best cost-ratio) for about 150 USD in used condition, so a similar rig like mine with all 7970s will cost you about 1000 USD with a power input of approximately 1300-1400 Watts when under full load. Over here, I have already sold my equipment, since you would need about 2 USD per ETH just to cover equipment and electricity cost and maybe refund it after a whole year (the rack needs to be maintained, too, don’t forget that! And it is likely to fail with changes, I had to tweak mine at least once a weak). Since you can buy 1 ETH at approximately 1 USD for now, it does not make sense to me. I guess you will need to put up your rigs in countries where electricity is really cheap (less than 10 cents per kWh) in order to have a very small benefit – and than you need to scale. All in all, mining is not worth it at all, imho. But it definately was, until the price dropped – and hey, I did not want to miss a chance 🙂

      1. Jacob:
        Regarding to ( I guess you will need to put up your rigs in countries where electricity is really cheap (less than 10 cents per kWh) ..
        We are in some African area we have low electricity $ <0.02 you are welcome to discus about to move forward, by the way i can also get my won rig, still i have some $k over for small investment… Have any idea? let's talk!!
        Good work!!
        Isam A. Abbadi

        1. @Isam Amin
          Price already went up again, so it’s profitable again. If you can get electricity that cheap, if I were you, I would have put a few rigs for sure 🙂

          Unfortunately, the POW period (ie. the period where you can mine ethers with graphics cards) will end this year, when ethereum will switch over to POS. So we’re talking about a timeframe of probably only a few months left 🙁

  15. Nice rig, I got almost exactly the same cards left from mining BTC/LTC
    so I am thinking to restart the mining again
    Just two questions:
    1. is it profitable mining Ethereal?
    2. are two 750w PSU a little pushing? as the system draws 1440w, almost 100%, are this safe and stable?

    1. 1. You mean Ethereum? Well, it depends on the electricity costs. In Germany, with about 30 cents per kWh it is not profitable.
      2. Here it also depends on the manufacturer. I discovered that the PSU wattage can have entirely different meanings from manufacturer to manufacturer. While two 850 W PSUs from Corsair handled the required power with high efficiency, staying very cool, two 1000 W PSUs I have also tested failed. So you really have to find out for yourself, but Corsair did extremely well among the PSUs I have tested.

      1. Hey jacob, are you from germany ?
        If so, I am from germany too and would love ask you some questions about your builded rig.
        Is it possible to contact you via email?
        Would love to build a similar construction like you have.

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