According to Youtuber who is in charge of repairing cards, it is due to mining and humidity

German Youtuber (KrisFix) who is dedicated to repairing PC parts has given an update on the abnormal number of Radeon 6000 video cards that failed a few weeks ago. If you weren't aware, several AMD Radeon RX 6900/6800 graphics cards (about 60 units overnight) were sent to the Youtuber for repair.

The Youtuber added additional information in his latest video where he explains that it seems that the driver has not been the reason behind which all these Radeon RX 6000 video cards died. Several of the users have bought these video cards from the same seller in the last two weeks.

It is suspected that these video cards have previously been used for crypto mining.

Although this could be the case, many gamers in other parts of the world have been using previously mined video cards and they haven't caused many problems, but KrisFix speculates that the environment where they were stored (humidity) may have been an important factor for them. these video cards fail in such a short time.

The Youtuber has invested 150 hours of testing to reach the following conclusions.

Vía: Videocardz