Can someone help me better understand GPU power usage

[bigjimmyauk]

So being a little energy conscious if I'm playing a game and it's running a stupid amount of frames per second does this relate directly to power use? Would say enabling vsync dropping a game from 144 fps to 60Fps lower power usage or would I need to manually adjust the core clocks and voltage. I'm on nvidia, I seen on my kids pc which has a AMD card it has something in the driver to automatically lower power usage based on frames and requirements but see nothing similar on nvidia.

I don't mind fiddling with afterburner etc but I see no reason my gpu should need to run at 2000+ mhz on every game I play.

 

[BUDFORCE]

I believe so.

Download hwmonitor it tells you how much power your card is drawing, then test it.

But yes it is my understanding to more FPS a card is pumping out the more power it will draw.

 

[ljt]

Lowering the frame limit can lower power consumption, but it is limited and unreliable. For example;

If you have a 144hz Monitor and "Game 1" isn't very demanding and can run at 144fps and uses 100% of the GPU to do it, then limiting that game to 60 fps will drop GPU useage down to 50% or less, and yes that will save power.

However, you then play "Game 2" which is very demanding and uses your GPU 100% but can only manage 70fps - limiting that game to 60 fps won't have such a drastic effect on power usage.

The best and most consistent way to lower power consumption on a GPU is to manually undervolt it using something like afterburners voltage/frequency curve.

 

[oguzsoso]

if you limit your frames nvidia driver may decide to underclock/undervolt gpu automatically if there's going to be enough performance headroom even with lower clocks

if you don't like the algorythm nvidia uses, you can use afterburner to create stop gaps between voltages and assign them to profiles like me

open afterburner, press CTRL+F to bring up the voltage/frequency graph

hold shift+left click to select the voltage points you want to flatten out

now stop pressing shift+left click. just lower the selected part with left click

now you locked the card to 868 mv 1710 mhz. you can do this for any voltage points. assign each curve to a certain profile (up to 5). pick any profiles based on the games you play


https://imgur.com/a/SHNInVT

final quirk: if you want to undervolt+overclock in the same time, before doing all the steps above, you can put a value between +50 and +125 to core clock

if you don't want to uv/oc you can omit doing this

 

[BUDFORCE]

I just discovered my card idles in windows at about 17w, my CPU 25w.

I wonder what the other bits idle at, 6 case fans, 360mm AIO cooler, 2 SATA SSD's one on the motherboard plus ram etc.

And monitor I suppose, not much though all together I would guess.

Anyway I am not really that bothered, apologies for going a bit off topic lol.

 

[chroniclard]

Could set various profile in Afterburner for different games, intensive game (max boost/power etc), easy game(undervolted/lower boost) if it really bothers you.

I have just underclocked my 3080 with a power curve, though not that fussed with power usage more about keeping it a touch cooler without losing much(if any) performance.

 

[oguzsoso]

for example, i know that this game will not stress the gpu beyond %70 core load at 1965 mhz with a 60 fps lock

yet nvidia driver decided to push max clocks with 114w consumption (i waited 5-6 minutes, it didn't downclock. i'm not criticising the algorythm here, its impossible for driver to know. its still relatively a high load so it wont downclock)



first stop; 1755 mhz + 0.9v (mind you, this is just pure underclock/undervolt, not an overclock+undervolt
power consumption is greatly reduced, performance is the same, core load is a bit increased



second stop; 0.85v + 1635 mhz (tad bit lower consumption(



most aggressive one; notice how gpu usage increased to %84. this might be a bit much aggresive. maybe an in between 0.8v would be better. but you need to test yourself if it causes any frame drops. i for one, never dropped frames at 0.7v - 1230 mhz in this particular game at 60 fps




in the end, a total of 45-55 watts is saved

 

[PrincessFrosty]

Bottom line is if you limit the GPU usage you'll save on power, and one way of doing that is capping the frame rate either through FPS limiting or vsync (but triple buffering needs to be disabled). As ljt pointed out if a game is running at close to that limit already then you wont see much benefit. Warning that vsync with triple buffering disable brings with it some minor latency.

You could have course turn down visual settings which makes it easier for the GPU to run the game and as such you'll get less GPU usage with a cap in place, but that would be kind of insane because you're now trading visual quality for power which goes against the point of powerful cards. In other words this mostly just applies to older games, or indie games which aren't very demanding graphically in the first place.

You can also experiment with undervolting the card using various tools, often hardware can run at slightly lower power than what they ship at which in turn lower power draw it also runs cooler and so fans run slower and quieter.

 

[bigjimmyauk]

Thanks for all the excellent input. Gonna have a play around with some settings tonight and see what we get