The real power from the wall will always be higher than what is displayed in your miner software. There are a few reasons for this.
With GPUs like the RX 470 the power consumption displayed there is only the GPU compute power and doesn’t include the memory controller power which is another 30-40 watts or so.
Another reason is the miner software has no idea how much power your motherboard, fan, SSD, cpus are consuming. These are usually 30-40 watts per system.
Another is your choice of PSU. You got a Good PSU with 90% efficiency it will use less power than a PSU with 75% efficiency.
Sorry if my question sounds dump, how will one know a PSU that has 90% efficiency? Isn't 400 watt draw a 400watt draw? Are you saying some power supplies can draw more than 400 watt draw if they are 75% efficiency? I will wait for a reply on this
Yes there is a difference. Different components inside the PSU determine how efficient it can be. The more efficient the more expensive parts it uses.
When a PSU says 400Watts, its the max power it can deliver to your computer. If the effiency is 90%, it means 10% is lost due to heat. So from the wall it might pull 440 Watts.
However the curve is most efficient when you are pulling around 50% load, so if you are maxing out the PSU, it might only be like 85% efficient and if you are only using 10% load it might also be 85% efficient. This is why there is usually a curve drawn on the box to show you this.
