It'd be enough for a quad core now, but I can't say how it'd do with a 9800 since nobody knows how much power they'll require. An HX520 would be a good investment if you're looking toward the future.
Again, the case is good enough for this rig, but I can't predict the mysterious future. The PC-7 is an excellent case and is a slightly better cooler than this Zen. The Zen, however, is a tremendous value. No other case in its very low price range comes close in terms of quality and performance.