Intel looked like a fallen giant. Now it's posting its fastest revenue growth in 15 years.

Intel CEO Lip-Bu Tan Bloomberg/Getty Images Intel posted its strongest revenue growth in more than 15 years. The company's data center and AI business grew 59% as the chipmaker gains AI momentum. The results sent Intel shares soaring in after-hours trading. Not long ago, Intel looked like a fallen giant. Now, the chipmaker has posted its "strongest revenue growth in more than fifteen years," CEO Lip-Bu Tan said Thursday. The company's second-quarter results sent shares up more than 11% in…