** Shares of Nvidia NVDA.O dip 0.7% as the heavyweight chipmaker's annual software developer conference gets underway, with investors expecting CEO Jensen Huang to defend his co's AI dominance as pressure mounts on major customers to rein in their heavy spending on the technology

** NVDA's devcon comes after China's DeepSeek spooked U.S. markets in January with a competitive chatbot it alleged took less computing power than rivals to create

** Co to unveil new chip system, Vera Rubin, despite production delays with predecessor affecting margins

** NVDA stock down ~10% YTD, underperforming Nasdaq .IXIC which fell 7%

** NVDA ~21% below 52-week intraday high of $153.13 reached on Jan. 7

** Stock recently traded at 26x expected earnings, below 5-year avg forward PE of 40, per LSEG data

(Reporting by Noel Randewich)

((noel.randewich@thomsonreuters.com))