I’ve built some Zcash Linux 6-GPU mining rigs using the Sapphire version of the AMD R9 Fury. I know the AMD RX480 is very efficient, but I feel the R9 Fury is better at mining Zcash. So I’ve been mining Ethereum on my RX480 rigs.
One of the nice things about GPU miners is their flexibility. I decided to put Claymore 11.1 Zcash mining application on the RX480 box, and compare the power usage to the R9 Fury box. At that point I could calculate electrical efficiency.
I know it’s possible to put custom BIOS’s on the GPU’s to improve the efficiency, but I don’t do that. First off, I’ve got too many other things going on with mining that I don’t have the time. Second, one of the benefits of GPU mining is the 2 year warranty on the GPU’s, and I don’t want to do anything to disrupt that benefit.
Zcash AMD GPU Card Test Results
AMD R9 Fury mining rate – 2515 H/s
AMD R9 Fury power usage – 1700 Watts
AMD RX480 8G mining rate – 1560 H/s
AMD RX480 8G Power usage – 990 Watts
It turned out to be closer than I thought! These systems both cost about the same to build. The R9 Fury system requires a second power supply, which adds about $60 more than RX480 build.
For long term operation, the efficiency is pretty close. Measuring it as H/s/Watts (bigger is better)
AMD R9 Fury efficiency – 1.52
AMD RX480 efficiency – 1.57
It would seem at first glance that future systems should be built with the RX480’s…but not so fast. Say we build four R9 Fury systems, for 10,000 H/s, at a price of about $9,200. This should earn us about $1000/month in Zcash.
The equivalent number of RX480 systems is a little more than 6 systems, for about $13,800. That’s $4,600 more for the same amount of hashing power. Over the course of a year, the efficiency of the RX480 systems would save us about $400 of electricity.
By building RX480 systems as Zcash miners, it would cost $4,600 more and save us $400. That’s not worth it, at all.
I will take my RX480 system and move it back to mining Ethereum, and keep the R9 Fury systems mining Zcash. And if I want to build more Zcash miners in the future, it will be with the R9 Fury boards!