Intel (INTC) announced Monday that chief executive officer Pat Gelsinger is retiring from the company and has stepped down from its board of directors.

Intel’s chief executive officer retired effective immediately, the legacy Silicon Valley stalwart announced Monday, a shakeup that follows an extended period of stock market underperformance for the semiconductor chipmaker. Intel’s CEO Pat Gelsinger retired effective immediately Sunday.

Shake up in Silicon Valley. Intel CEO Pat Gelsinger announces immediate retirement with the company naming two interim co-CEOs to lead the chipmaker. He started at Intel in 1979 and was its first chief technology officer.