The GPU leader is still a top stock to own, but Dell's upside could be much higher.Nvidia (NVDA 8.15%) now has a market cap of about $2.5 trillion, making it one of the most valuable companies in the world. The stock has enjoyed an incredible rally in the past couple of years, and even though it has been declining in recent weeks, it's still up by an amazing 115% since January.While there are plenty of opportunities for the leading artificial intelligence (AI) chipmaker's business to grow, because it now tr ...