It's currently better in 99.9% of games. So yes. Not to mention that even in games where all of the cores of the FX are used the i5 can still match or beat it.
If you can't afford an expensive motherboard, have a look at the Xeon 1230v2 or v3 and you can pair it with a B or H series motherboard which are far cheaper than the Z series. The Xeon matches the performance of a high end i7 (3770/4770) of the same generation. They tend to be priced far lower than the i7s.