jimmyEatWord :
i was thinking of getting an m5 z270 msi motherboard although i'm not sure if you can overclock your cpu with it or just the RAM
all because i don't have enough money to upgrade to kaby lake , of course my other option is to buy a kaby lake i7 instead of those two and use it on my z170 mainboard ..
Every Z-series MoBo offers CPU OC.
With Z170 chipset, you may need to update your BIOS prior to upgrading CPU to Kaby Lake family.
Just check the BIOS version you have and confirm from MoBo manufacturers site if your version of the BIOS supports 7th gen CPUs or not. If it doesn't, update your BIOS to the version that supports 7th gen CPUs.
Note: If BIOS update process gets interrupted, you can brick your MoBo.