As these reports note, miners are removing the stock cooling systems from GPUs to install a third-party solution or recently tried to resolder failed GPU dies back in place and paint the yellowish GDDR memory chips. According to the testing done by Iskandar Souza, you can see below the difference between a worn-out yellowish GDDR chip and its painted deception standing next to one another.
https://www.techpowerup.com/304045/crypto-miners-paint-gddr-memory-chips-to-hide-wear-and-tear
Not only did they screwed us once, they try to do it twice!