Power draw

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Can someone give me a quick and dirty lesson in undervolting a gpu to reduce power consumption. Im running xfx Rx580 8g black edition. With 5 running Im drawing 1060w on a 1200 power supply. I know everyone gets the power draw reducedbut how? This is all new to me.
 
With the overclocking software (usually MSI Afterburner) you lower the core voltage by mV increments. Or you can lower power limit percentage. Most ppl use the percentage. Then lower it by 5 and see how stable the system runs for about 30mins or so. If that works, drop it another 5%. If it starts giving issues, then bump it up 1% until it becomes stable.
All this while you can bump the Memory speed up (not necessarily gpu speed) will help get better performance, stable results, lower power consumption.

This is, of course, super quick explanation and I may be off. I'm sure mike will chime in with more details, but this is how I understand it.
 
I used wattman and lowered the gpu voltage -10 and power is down to about 780w but mh fell to 25.5. I went back to stock settings and mh didnt increase at all. Still at 25.5 . Not sure whats going on.
 
First off, what was your starting hash rate?

The whole idea of underclocking is to reduce quite a bit of energy consumption with little impact to hashing. The hashing can drop, however, it will not drop as fast as the power consumed. So in the end, your net is higher over all.

So, let's say you have 30H/s and consume 1000W. Lowering consumption to 700W but dropping to 25H/s
30H / 1000W = .03H/W
25H / 700W = .0357H/W
In this example, we see that the number of hashes went up per watt consumed. This is ultimately your goal when underclocking.
 
I bumped the memory up to 1925 MHz from 1725 and they are all running at 28.3 mh. Ill let that run for a day or until it crashes and see what happens


I bumped the memory up to 1925 MHz from 1725 and they are all running at 28.3 mh. Ill let that run for a day or until it crashes and see what happens. I was originally at 30.5 after bios mod.
 
It's all in the fine tuning change from 1925 to 1920 re test - power v hash v heat, then start again do it all in a excel spread sheet. What OS are you mining with ?
 
Windows 10 pro. I have Ubuntu but Im just not that familiar with it. Im feeling my way around with this first miner while i wait on my other gpus come in. I have to admit, the learning curve is a little more envolved than I thought but I love learning new things and Im having a lot of fun doing it.
 
hbpowerwall said:
It's all in the fine tuning change from 1925 to 1920 re test - power v hash v heat, then start again do it all in a excel spread sheet. What OS are you mining with ?

That is exactly the way to go. The less heat, the longer your cards will last too. In many cases the core goes faster than the memory can keep up with, in the case of compute operations.

I don't mine, but even for games, if a game does not need the full potential of my card, I underclock and undervolt it.

The 'quick and dirty' lesson, as clock speeds are reduced, power consumption is reduced exponentially. So put simply if you drop your clock by 25% the power required by that core should drop to 50%. In reality this is not the case, it really depends on the quality of the core itself, and the efficiency of the voltage regulator.
 
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