I know I'm responding to something a bit old here, but I need to caveat this for those not in the know:
I'd keep away from even a fifth or sixth generation i5 at this point unless you're willing to purposefully shut off certain Spectre-mitigations (which is itself somewhat dangerous) because the performance hit is pretty insane.
Spectre and its boatload of offspring are a real source of frustration and will continue to be so for a good long while. I won't be surprised if the entire existing i3/i5/i7/i9 line to this point ends up being a dead end like the Pentium 3 just because of the Spectre side effects being too severe.
Try checking the MAME manual at http://docs.mamedev.org