Archive for  May 2016

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After a lot of testing, we recently started building our ethereum GPU mining farm. These are the first rigs we have been building up.

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If you’re interested, get in touch for us for a complete parts list and detailed instructions on how to build and run those at jacob@omg-it.works. There are different configurations possible, depending on your personal situation.

A lot of people are asking about the various graphics cards one can use for mining ethereum. Theoretically, all AMD cards with 3GB or more of video memory can be used, but if you look at the price and efficiency concerning power consumption, there are just a few cards left. Within this article, I’d like to go deeper into the specific cards, so here are our top favourites:

Radeon 7950/Radeon 7970

7950_7970

The Radeon 7950 and 7970 cards can mostly be bought used for a current price of 130-170 EUR. They draw 200-250 Watts, depending on the model and clocks and need two PCI-E connectors. Also depending on the model and they can make up to 25 MH/s, but mostly will reach around 21-22 MH/s, whereas more powerful cards will draw more power, of course.

Radeon 7990

7990

Technically, the 7990 is two 7970 cards packed closely onto one PCB. This is why it will be recognized by the system as two separate 7970 cards. This yields a theoretical hashrate of 50 MH/s. We have tested several 7990 cards, but the results are disappointing. The air cooling is just not sufficient and the card has massive heat problems. Since it will be recognized as two cards, you will also never be able to run more than 4 of those cards in a rig (since the AMD driver will only allow up to eight cards). The only viable solution would be water cooling, but that might be too pricey. You can buy this card used for about 300-350 EUR.

Radeon R7 370

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As we were looking for newer cards, we came across the R7 370 4GB. This card can yield 14-17 MH/s, drawing around 150-170 Watts. The practical thing about this card is it comes with a single PCI-E power connector, so a single 1000 Watts power supply may be sufficient to power a rig with 6 cards. However, you should be aware there can be some differences between card manufacturers that may impact performance. Just make sure to buy the 4GB version, not the cheaper 2GB, which will not work at all. For such a card you will pay around 140-160 EUR.

Radeon R9 nano r9_nano

Don’t underestimate the capabilities of this card. By undervolting, it is possible to have this card running well below 120 Watts power consumption while yielding a hasrate of about 25 MH/s, which makes it as twice as efficient as other cards. Unfortunately, this card is pretty new and it is not cheap. You will pay at least 450 EUR, so it really depends on your calculation if you plan using these cards in your rigs.

Conclusion

If electricity is cheap, I’d always go in for the 7xxx series cards. If you need quite a lot of them, you’d probably better off with buying R7 370 4GB cards because of the better availability. However, if electricity is not cheap, you might think about buying R9 nanos. After all, there is no such thing as the perfect card for mining, there are advantages and disadvantages depending on your budget and location. If you need professional help building your own rigs, you might always contact us.