AMD (NASDAQ: AMD) mounted a stunning comeback over the past 18 months, surging from less than $2 a share last February to about $13 today. The chipmaker repeatedly defied the bears — who claimed that it would be crushed between Intel (NASDAQ: INTC) and NVIDIA (NASDAQ: NVDA) — by pivoting toward SoCs for gaming consoles and launching new CPUs and GPUs that addressed previous shortcomings.