Results: Modifying GPU Frequency
While the Ethash algorithm is more sensitive to graphics memory performance than GPU clock rate, a certain amount of compute power is still necessary. Therefore, we thought it would be interesting to measure how the GPU's frequency affects hash rate, and, by consequence, the graphics card's power consumption. After all, with GPU voltage tied directly to each chip's clock rate, reducing both generally facilitates a nice savings in power. That might not mean much in a gaming PC, but mining rigs with lots of graphics cards under full load are particularly sensitive to power, heat, and cooling.
Power measurements were taken at the wall outlet by subtracting the rest of the system's consumption (observed to be 45W) under load. By maintaining the same scale on different charts, we're able to draw comparisons between cards.
Preliminary Observations
- Even reduced to a minimum of ~400 MHz, the GeForce GTX 1060's GPU frequency is still higher than the point at which hashing performance starts dropping. To further improve performance/watt, you'd probably need to manipulate the card's power target.
- The consumption of MSI's GeForce GTX 1060 6GB doesn't vary much at all. This can be blamed on the GPU's voltage, which remains constant regardless of the GP106's clock rate.
Analysis
- The hash rate does not drop as GPU frequency is lowered. This holds true up to a certain point, after which the processor's compute performance cannot keep up. From there, it becomes possible to dial in an optimal clock rate (and optimal voltage) for each card's GPU, minimizing power consumption as much as possible and maximizing efficiency.
Your mission, should you choose to accept it, is to find a GeForce GTX 1060 6GB that'll take an aggressive GPU underclock and bring its voltage down as far as possible. If you pick a Radeon card instead, manually set the GPU frequency to ~1 GHz, though it may be necessary to aim higher if you choose to overclock the graphics memory.
MORE: The Ethereum Effect: Graphics Card Price Watch
MORE: How To Mine Ethereum Now
MORE: Experiment: Build a (Profitable) Ethereum Mining Rig From Spare Parts
MORE: Top 25 Cryptocurrencies By Market Cap
MORE: Best Graphics Cards
