NVIDIA Corporation (NASDAQ: NVDA) stock is up nearly tenfold in the past three years. But with the company set to report second-quarter earnings after the market close Thursday, at least one analyst believes the company should be worth about half of its current market value.

Nvidia bears have gotten plenty of egg on their face in recent years, but BMO Capital Markets analyst Ambrish Srivastava is digging in his heels on Nvidia ahead of earnings. In a new report out Monday, Srivastava acknowledged the potential for upside earnings revisions in the near-term but reiterated his belief that Nvidia’s valuation is unsustainable in the long term.

Srivastava reiterated his Underperform rating and $85 price target for Nvidia, suggesting roughly 50-percent downside ahead.

“We are staying with our Underperform rating as we believe at a P/E of 52x and an EV/FCF multiple of 46x vs. 15x and 16x for the group, respectively, NVDA's valuation is unsustainable at current levels,” Srivastava wrote.

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With respect to Thursday’s reports, BMO is expecting Q2 earnings per share of 67 cents on revenue of $1.95 billion, slightly below Wall Street consensus of 70 cents and $1.96 billion, respectively. Looking ahead to the third quarter, BMO is calling for EPS of 75 cents on revenue of $2.11. Consensus estimates forecast 79 cents and $2.14 billion.

In the second quarter, BMO estimates Nvidia’s Gaming segment revenue was down 3 percent quarter over quarter. In addition, BMO is calling for a 14-percent quarterly increase in Datacenter revenue, a 13-percent increase in Professional Visualization revenue and a 2-percent increase in Auto revenue.

“We believe that the perfect storm in fundamentals that drove the rarely seen magnitude of earnings upside is ebbing,” Srivastava wrote.

He also added that the market is not fully appreciating Nvidia’s artificial intelligence and machine learning competition.