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Comment by jacquesm

19 hours ago

This one is real, but there are some caveats:

- you will need to run your card hotter than you might be comfortable with

- the real pay-off (on some cards, apparently, see downthread) requires increasing the maximum power to 450W

- This is well above what the stock cooler was designed for so a bit more cooling would help

What's nice is that you can stack this mod on top of (or rather, below of, this one loads first) the p2p mod that has been out for a while, they don't seem to interfere with each other.

11 comments

jacquesm

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Zagitta  18 hours ago

It's quite nuanced. In a nutshell the unlock just flips the 2 bits that halves how often the core can issue the specific instructions Nvidia locks to full rate on the professional and datacenter cards.

Obviously doing more compute requires more power but what it does is shift the card down on the frequency curve to keep the wattage in check. So you're right that at stock power limits it hits a cap where the full issuing rate isn't reached but it depends heavily on the exact workload how much juice is left.

The frequency curve also takes heat into account so in general you end up with a nice perf boost for a slightly hotter card.

I've been running this on my 2 3090s for a month now with no issues but they are also water cooled :-)

  • jacquesm  18 hours ago

    Ah, that's a twist I didn't see coming, all my GPUs are aircooled. I can see how with watercooling you'd be able to get more performance out of the GPU before hitting the limits.

  • BoorishBears  16 hours ago

    There 3090 is from the era of overclocking, anything but the reference design should be fine even on air cooling (especially if you have a 3 connector model)

    My EVGA came with stock firmware that started at a 420W and allowed up 500W, of course 500W did nothing for gaming

Tiberium  18 hours ago

> - you will need to run your card hotter than you might be comfortable with

Can you explain this one? On my GPU I didn't have to change the power limit. Obviously the card might spend more time at max power usage, but it's still within the limit.

  • jacquesm  18 hours ago

    If you increase the power limit on the card you will be able to get much more mileage out of this modification. At 450W the difference is much, much larger but that is not something I'm comfortable with doing for longer runs. Note that the stock settings are already pretty extreme for that cooler, and that ambient temp and free airflow are going to be impacting the resulting GPU temp in a very direct way. I have my 3090's in an external box (with its own separate PCIe backplane) so they can talk p2p and have 'fresh air' rather than in the enclosure.

    • Tiberium  18 hours ago

      Yes, but you can get up to a 40-50% increase in some workloads even with the same power limit, and some cards have it locked anyway. I just felt like it was a litle misleading for you to mention the power in your original post, since the unlock works regardless of that.

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