that motherboard is a 4+1 design... so no... i would not advise aggressive overclocking with it.
As to max overclocks... that depends, chip to chip... and how robust your cooling solution is. with an h100i you'll need a little luck on the draw with the cpu. That said, with a good motherboard, solid motherboard, and a decent psu, you should be able to get a 8 cored fx up to 4.7ghz at least.
past that point it will be all luck. if you're lucky you'll get to 5.0ghz... but some chips just won't do it without a more robust cooling solution (like a DIY custom water cooling system). My 8320 hit 5.0ghz on a Asus m5a99x Evo motherboard, with a h100, and XFX Pro 750W psu. But by most respects, that's a golden chip; I got a little lucky.
Anyway, hope this fills in a few blank spots.
here is a list of motherboards. you'll want a 8+2 power phase design PLUS heatsinks on the vrms... the lone exception is with an Asus motherboard... the 990 chipset asus boards all use digivrm, which are extremely high quality, those are good enough with a 6+2 setup.
Generally you'll want to avoid asrock and msi motherboards as they use crappy vrms, which tend to blow up under serious overclocking loads (this is for AMD motherboards, both companies make solid intel boards)