Advanced Micro Devices shares fell for a second-straight day after the firm's new Ryzen line of desktop processors disappointed gamers.

"The [Ryzen] 1800X lags behind its Intel counterparts in gaming, regardless of whether it's running at the same clock speed or higher," Mark Walton wrote in technology review site Ars Technica on Thursday.

PCWorld, PC Gamer also criticized the new processors for poor gaming performance.

Shares of AMD closed down more than 6 percent Friday after falling 7 percent Thursday. Intel shares closed little-less-than one percent lower Friday.