It's time for investors to pay attention to IBM stock.Artificial intelligence (AI) has driven huge returns for investors, particularly in a select few large-cap stocks. Every stock in the "Magnificent Seven" has benefited from the technology, and some smaller players have also earned outsized returns.Amid such gains, investors may forget that some of the oldest tech stocks in existence have made notable pivots into AI. Knowing that, it might be time to pay particular attention to the comeback in Internation ...