(Bloomberg) — While mention of ties to Nvidia Corp. still sparks big jumps in shares of companies around the world, the gains can prove to be short-lived and some investors are questioning whether the halo effect is fading.Most Read from BloombergThese Homes Withstood the LA Fires. Architects Explain WhyAs E-Bikes Boom in NYC, Some Call for More RegulationsA Blueprint for Better Bike LanesSamsung Electronics Co.’s stock gained over 3% last Wednesday after Nvidia founder Jensen Huang expressed c