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Comment by ftufek | Hacker News Reader

For what it's worth, you can power limit them and I'd highly recommend it if you plan on running a few of these. In the past we've power limited RTX 3090s to 250W (100W lower than original) while losing negligible amount of performance.

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Do you just limit using something like MSI Afterburner?

I was undervolting and underclocking my Titan XP for a long time (with a separate curve for gaming) but lost the config and have been lazy to go back. I mainly did this because it has a mediocre cooler (blower design that is not nearly as good as the current ones but also not terrible) and even at low usage it was producing a lot of heat and making some noise (the rest of my system I specifically designed to have super low noise).

I just used `nvidia-smi -pl 250` on linux, it's built into the driver itself, I'm sure there's equivalent tools (or maybe even nvidia-smi itself) for Windows as well.

I'll also add that Nvidia's drivers are fairly good at keeping wattages relatively low, at least for desktop cards. My 3070 will idle ~10 watts when decoding video or just accelerating my desktop environment. You only see that 300-watt TDP take effect when doing consecutive renders or local ML like Stable Diffusion, and you'll definitely want the extra power.

The fan curves though kinda suck for the default nvidia drivers - especially on the blower it will run them super low to try to make it silent (which is not very efficient heat wise) and then not start spinning it up until it is really under load. Whereas there is a level that is barely an increase in perceptible noise that cools the GPU significantly more and for many mid range loads will not end up with with the GPU temp (and the fan) going through lots of highs and lows.

Interesting - going to look into this - do you set custom fan curves at all? Wondering basically if I can use a command like this to set a ceiling on wattage and then a second command to set an increased lower limit on fan speed.

Nope, I don't touch anything else. This is essentially telling the GPU, don't use more than this power at all, it'll automagically figure out the best configuration and all that. I've ran those power-limited rigs for 24/7 for many weeks, no issues at all and reduced heat is a nice side effect.

There's literally a power slider now. So yeah just fire up Afterburner, take the power slider, and lower it as much as you want until performance falls off too much for you. I think you can drop all the way to 50% or something somewhat asburdly low (at which point you should probably have just bought a cheaper, lower-power card in the first place)

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