Many rumors have been floating around lately claiming that AMD’s Big Navi graphics cards will be as much as 1.5x faster than the NVIDIA Ampere flagship, the RTX 3090 in crypto-mining. Before you start panicking, we have some good news for you. No, the Radeon RX 6800XT and the 6900XT won’t be 1.5x faster than the RTX 3090, or maybe even the RTX 3080 in terms of the mining hash-rate. As a certain Twitter user points it out, the mining performance is largely based on the GPU’s raw memory bandwidth.
All the top mining cards in the past, including the Radeon VII and Vega 56/64 had a massive bandwidth, thanks to the use of HBM memory. The reason why the RTX 3080/3090 are a notch above the Turing lineup in mining performance is due to their higher bandwidth (GDDR6X + wider bus), rather than the increased shader count (they do help, but not as much).
Mining usually involves large data-sets that perform better on GPUs with enhanced compute performance (GCN), and as we mentioned, wider bandwidth, as you have to move all that data around. So, no, the RX 6800XT or the 6900XT won’t be beating the RTX 3080/3090 in crypto-mining by 1.5x. They may perhaps level with them or just outperform them, but our money is on the former.