Before jumping to our coverage of the tests, it should be mentioned that there are two versions of Radeon RX 480. The cheaper option has 4GB of video memory that operates at 7 Ghz clock frequency. The more expensive model has 8GB of video memory that works at 8 GHz.
Running tests on Radeon RX 480 8GB
Since we have been testing ASUS Radeon RX 480 8GB operating at 8 GHz, this post provides results for Ethereum mining with this particular card. The 4GB model operating at 7 GHz will mine approximately 2-3 Mhs slower than its 8GB/8 GHz counterpart. When looking to purchase equipment for Ethereum mining, consider 8GB models.
We were using Claymore Dual Miner’s default settings: graphics processor frequency at 1266 MHz and video memory frequency at 8 GHz. We were able to achieve about 24.7-24.8 MHS with the estimated power consumption at 108W and real power consumption at 177W. Given the productivity of 80 Plus Gold PSU, the card’s capacity amounted to 150W at default settings. Our figures were further confirmed by the fact that mining Ethereum at default GPU frequency keeps it at about 1240 MHz never reaching the maximum of 1266 MHz.
Once the power limit of 150 watts (for which the card is designed) is reached, exceeding this limit by just several percent allows for a full boosting of the GPU to a total of 1266 MHz. This is not that important for Ethereum mining but may actually be of significance for other algorithms which are not that sensitive to the video memory.
Dual mining enables us to mine Ethereum and Decred simultaneously: 24.3 MHS for Etherium and about 365 MHS for Decred (at a default intensity of 30). Eventually, we increased intensity for Decred to 35 which reduced Ethereum hashing capacity to about 24 MHS and increased the Decred hashing power to about 450 MHS. Therefore, we were able to confirm that RX 480 is an excellent choice for dual mining. A slight reduction of the hashing power for Ethereum mining results in subsequent growth of Decred mining capacity.
The next step was to boost the card. The only thing we managed to achieve was maximizing the operational frequency of the video memory which in our case was 9 GHz (the card could provide even higher frequency, however, the software or drivers used for boosting have their limitations. Therefore, 9 GHz is the upper limit). Operating at 9 Ghz, RX 480 produces about 28 MHS of the hashing power when mining Ethereum.
It’s quite possible that the hashing power may produce even better results in case the 9 Ghz limitation for the video memory is overcame. However, neither the AMD’s WattMan, nor the Asus tools enable us to do this right now. Boosting the video memory increases the power consumption by 7W-8W and it’s absolutely worth doing when mining Ethereum.
The fact that the GPU clock could not be boosted was a bit disappointing considering that it has the capacity of reaching 1340 MHz. Of course, boosting does not impact Ethereum mining. In fact, if you solely focus on Ethereum mining, the clock frequency of the GPU should be slightly lowered. At the same time, we were not particularly happy with RX 480’s cooling system. AMD fan settings leave the card quiet, yet very hot which is not the best solution for mining.
We found that the best fix would be to set the rotational speed of the fans to 80%. This would allow us to achieve moderate temperatures and avoid noise. This is a good decision if noise is a significant issue for you. By setting the rotational speed of the fans to 80%, you can expect about 72℃ of the GPU which is not entirely satisfactory for round-the-clock mining. At the same time, increasing the speed of fans to 100% significantly boosts the noise, and results in the subsequent reduction of the temperature to 68℃, i.e. not that much.