Slaven Vlasic/Getty Images for The New York Times; Chelsea Jia Feng/BIBank of America analysts raised their price target for Nvidia stock to $190 a share this week.They see the AI market growing to $400 billion, giving Nvidia a "generational opportunity."They point to Nvidia's strong lead among competitors, helped by its enterprise partnerships.Nvidia stock has been on a tear all year, but investors can brace for even more gains ahead, Bank of America analysts say.In a Thursday note, the analysts raised their price objective on the stock from $165 to $190.