I've 2 RX 6700 XT. It's a dual GPU setup.

1st one gets hot like hell because of the hot air it takes from the 2nd and the 2nd still runs a bit too hot.

The 1st one becomes so hot that i can't run the project since it goes in thermal throttling.

Hard to give some advice without knowing how your system is cooled, but in general you need to push more air through the system and in particular between the cards. Some people use risers to get more space between the cards.

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