It seems like pretty much every AMD card in existance benefits HEAVILY from undervolting! Better than overclocking, actually. This tutorial works for the RX 6700 and RX 6700 XT (Also, if you're reading this and have a 6700 non-XT, just flash the BIOS to be a 6700XT and you'll thank me later) but the values are very similar for the RX 6600 as well, with the RX 6600M being in the same boat.
Here's a link to the benchmark used in the tuturial: https://benchmark.unigine.com/heaven
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