Bernstein downgraded semiconductor stock Nvidia on Monday to market perform from outperform, saying the company is facing severe challenges to growth and "headline risk [is] likely to continue increasing."

"Following the company's somewhat chilly guidance cut ... we believe the shares are likely to remain hamstrung," Bernstein analyst Stacy Rasgon said in a note to investors.

Ahead of earnings on Thursday, Nvidia cut its revenue guidance for the fiscal fourth quarter. The company cited "deteriorating macroeconomic conditions, particularly in China," for the lowered forecast, which was Nvidia's second cut in the past three months.

"The latest cut appears much more fundamentally demand-driven, with the question of the 'true' run-rate of the gaming business remaining up in the air for now," Bernstein said.

Nvidia shares slid 1.2 percent in trading Monday to close at $146.45 a share. Bernstein has a price target on Nvidia of $175 a share.

After five years of monster gains, the hot stock cracked in 2018. The shares are down more than 40 percent the last six months.