More enthusiastic customers sounds like good news for the chipmaker, but there’s a problem: Crypto mining demand is unpredictable and may not be sustainable. These buyers tend to take flight as soon as coin prices drop. Back in 2018, surging Ethereum prices similarly led to graphics-card shortages. When the price of cryptocurrency collapsed later that year, miners flooded the second-hand marketplaces with used cards, hurting Nvidia’s business. In late 2018, the chipmaker’s stock price sank after it surprised investors with financial guidance significantly below Wall Street expectations.