** U.S.-listed shares of chip designer Arm Holdings ARM.O rise 4.7% to $135.89 premarket

** HSBC upgrades to "buy" from "reduce," raises PT to $205 from $90

** New PT represents a 59.7% upside to the stock's last close

** ARM is shifting to being a core AI server CPU player, and brokerage expects industry CPU shipments to grow by 20% in 2026 and 21% year-on-year in 2027

** HSBC says server CPU royalties could be as big as the company's current topline by 2030

** "We believe Arm's server CPU royalty revenue could grow at a CAGR of 76% from FY2026-31" - HSBC

** Avg. rating of 40 analysts is "buy;" their median PT is $150 - data compiled by LSEG

** Up to last close, stock has risen 18.8% this year

(Reporting by Anhata Rooprai in Bengaluru)

((Anhata.Rooprai@thomsonreuters.com))