Early tests on cards that are already circulating among miners indicate it's a BIOS-level protection. PC Gamer has some more info and reports NVIDIA is confident that its limiter cannot be hacked. The GPU maker also confirmed this limiter will not be rolled out for existing cards.
Specifically, Nvidia tells PC Gamer that it believes "the software cannot be hacked to remove the limiter."It will be interesting to see if AMD chooses to follow the same strategy with its upcoming Radeon RX 6700 series.
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The RTX 3060 will be the only card to come with the limiter in place from its arrival on February 25, Nvidia tells us, as it is "not limiting the performance of GPUs already sold."