Nvidia to fall nearly 20% on increasing competition from AMD, high valuation, analyst says

A Nvidia Drive PX 2 computer for autonomous vehicles.
Steve Marcus | Reuters

Instinet lowered its rating on Nvidia to reduce from buy, saying the company's earnings will come in below expectations this year due to a more difficult gaming graphics market.

"We believe consensus is underappreciating a slowdown in gaming and the potential negative impact to the multiple," analyst Romit Shah wrote in a note to clients Wednesday. "We recommend investors take profits."

Nvidia shares are up 251 percent in the past 12 months due to better-than-expected sales results from its graphics card segment.