Lenovo’s making inroads in a field not normally associated with the Chinese company: showier gaming computers. The world’s No. 2 PC maker, long a specialist in workman-like computers, has over the past year touted a Legion line that’s held its own against the hyper-fast liquid-cooled machines offered by Dell Inc.’s Alienware and its ilk. It’s now a $1 billion business, helping Lenovo Group Ltd. grow revenue by the fastest pace in more than two years last quarter. Its shares rose 6.9 percent Friday, their biggest gain in almost two years. Emboldened, the company intends to plow more resources into gaming as it struggles to convince investors it can once more deliver the sort of growth that made it China’s global tech standard-bearer a decade ago. Chief Operating Officer Gianfranco Lanci credits a tactic of targeting the growing legions of casual enthusiasts that spend a few hours daily on their favorite titles rather than the diehards. “This is where we’re really trying to address. Because to compete with Alienware, this market is not growing too much. And you need a very different point of view,” the Italian executive said in an interview. “We took a different approach, frankly speaking. When you…